And that's a wrap. Thanks for your company and hope to see you tomorrow when we can do it all over again before waving goodbye to Jerez for another year. Until then, it's good afternoon from me. Adios!
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ReutersCopyright: Reuters
Lewis Hamilton will swap his bike for the Mercedes W06 tomorrow for the final day of this first test in Jerez. Jenson Button will be in action, too, as will Romain Grosjean, who will get his first go behind the wheel of the new Lotus.
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So an encouraging day for McLaren, albeit it one which was curtailed because of an engine issue. Mercedes will be pleased with another 150 laps in the bag, which brings Nico Rosberg's lap total this week to an staggering 308.
Sauber and Toro Rosso managed more than 100 laps, too, while Ferrari and Lotus almost made the century. It was less successful for Red Bull who missed much of the day before a late flurry of laps from Daniel Ricciardo.
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Mercedes: That's a wrap for @nico_rosberg @circuitodejerez! Nice touch on his in-lap radio: "Thank you everyone - really top job to start to the year".
Day three results
1) Felipe Nasr (Sauber) 1:21.545 108 laps
2) Kimi Raikkonen (Ferrari) 1:21.750 92 laps
3) Nico Rosberg (Mercedes) 1:21.982 151 laps
4) Felipe Massa (Williams) 1:22.276 71 laps
5) Pastor Maldonado (Lotus) 1:22.713 96 laps
6) Carlos Sainz Jr (Toro Rosso) 1:23.187 136 laps
7) Daniel Ricciardo (Red Bull) 1:23.901 48 laps
8) Fernando Alonso (McLaren) 1:35.553 32 laps
Chequered flag
PACopyright: PA
Felipe Nasr finishes fastest on day three of pre-season testing in Jerez.
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Can you guess who is responsible? Yep, it's Pastor Maldonado, whose Lotus has rolled to a halt.
Red flag
With one minute to go, we have a red flag!
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Still no signs of any improvements at this stage, with Pastor Maldonado completing his final run before handing the car over to Romain Grosjean, who has yet to drive the car, for the last day of the test.
Ten minutes to go
It's busy out on track with seven drivers circulating - Nico Rosberg, Daniel Ricciardo, Kimi Raikkonen, Felipe Massa, Felipe Nasr, Pastro Maldonado and Carlos Sainz Jr. Ten minutes to go.
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Fernando Alonso and McLaren have completed the fewest laps of anybody today with 32, with Red Bull's Daniel Ricciardo only having achieved fractionally more at 35 so far. At the other end of the spectrum, Nico Rosberg is up to 145 laps, with Carlos Sainz Jr next up on 124.
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BBCCopyright: BBC
F1 journalist Dan Knutson in Jerez: "Pit stop practice during a long run of laps by Nico Rosberg. The Mercedes W06 is covered in green flow-vis paint, so the mechanics will have lots of cleanup to do tonight."
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Sauber: Felipe Nasr is still on top of the time sheet, now on a longer run.
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Kimi Raikkonen has been joined by Felipe Nasr, Nico Rosberg and Pastor Maldonado as we approach the end of the session. No one coming close to beating the benchmark time set by Nasr.
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F1 journalist Dan Knutson in Jerez: "Kimi Raikkonen is doing a long run. A Ferrari crew member showed him a pit board indicating 15 laps to go."
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Kimi Raikkonen has the track to himself with 40 minutes remaining. The Finn has managed over 70 laps, today. Only Nico Rosberg and Carlos Sainz Jr have crossed the century mark.
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BBCCopyright: BBC
F1 journalist Dan Knutson in Jerez: "The Sauber crew didn't bother putting the usual screens, so here's a shot of the fastest driver and car at the moment - Felipe Nasr and the Sauber - in the garage."
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MercedesCopyright: Mercedes
Mercedes: @nico_rosberg departs the garage with an almighty sneeze for another run...
One hour to go
Just 60 minutes remaining of today's session, with Felipe Nasr heading the timesheets, two tenths clear of Kimi Raikkonen's Ferrari.
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Daniel Ricciardo pops into the pits and then heads straight back out. It looks like the Red Bull might finally get a decent run of laps under its belt before the day is out.
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Pastor Maldonado is still out there, along with Carlos Sainz Jr, Felipe Massa and Daniel Ricciardo.
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Fernando Alonso: Big step forward... #McLarenHonda #proud #Progress
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BBCCopyright: BBC
F1 journalist Dan Knutson in Jerez: "Work has been going on behind the screens in the Red Bull garage for most of the day.
"With Daniil Kvyat doing 18 laps yesterday and Daniel Ricciardo doing just 12 so far today, it really has been a couple of wasted days for the team as far as getting mileage on the car is concerned."
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Pastor Maldonado goes fourth quickest for Lotus with a 1:22.950, 1.4 seconds off the pace set by Felipe Nasr in the Sauber.
BreakingHeadlines
Here are the day's headlines:
McLaren end day early because of power unit problems, but they managed 32 laps
Felipe Nasr sets the pace for Sauber after track dries in Jerez
Nico Rosberg clocks 120 laps, but loses time after stopping out on track
Nasr spins, bringing out the first red flag of the day
Lotus delayed because of telemetry issues
Red Bull endure tough day with limited mileage after engine change
Listen to the McLaren-Honda
Want to know what the new McLaren-Honda sounds like? Thought you would. Click here to hear a comparison between that and the Mercedes.
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Hurrah, Ferrari fire up their car and send Kimi Raikkonen on his way, with Nico Rosberg and Felipe Massa following him down the pit lane.
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The track falls silent.
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Red Bull: Hitting all the notes, just not necessarily in the right order... That's testing!
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ReutersCopyright: Reuters
Lotus are having an encouraging day with Pastor Maldonado passing his half century of laps before heading back to the pits for a few tweaks to the car.
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Williams: Felipe reports the track is improving as he completes an eight lap run, taking his total to 47 for the day.
Two hours to go
With two hours to go, Felipe Nasr heads the timesheets with a 1:21.545, 0.8 seconds clear of Kimi Raikkonen's Ferrari. Mercedes' Nico Rosberg is third, four tenths adrift.
Felipe Massa is fourth, ahead of Daniel Ricciardo, Pastor Maldonado, Carlos Sainz Jr and Fernando Alonso.
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F1 journalist Dan Knutson in Jerez: "Like the rest of the teams, Williams plan to put a number of upgrades on their car. Williams will run their Australian Grand Prix spec car, or something very close to that version, at the last pre-season test.
"'We are going to see changes between now and Melbourne,' chief technical officer Pat Symonds said. 'You will see them in the final days of the final Barcelona test.'"
Nasr back on top
But back comes Felipe Nasr, the Sauber driver clocking a 1:21.545 to bump Kimi Raikkonen down to second. We shouldn't read anything into this really, as we don't know what fuel loads they're running while different tyre compounds will also have an affect, too.
Raikkonen goes quickest
Getty ImagesCopyright: Getty Images
It's straight down to business for Ferrari's Kimi Raikkonen as the Finn pumps in a 1:22.351 which sends him flying to the top of the timesheets.
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Break over at Ferrari as Kimi Raikkonen heads back out on track, with Williams' Felipe Massa and Sauber's Felipe Nasr for company.
Recap
EPACopyright: EPA
Nico Rosberg's Mercedes spent some time on the back of a truck earlier today when the engine broke down during the German's run.
Nasr reclaims top spot
PACopyright: PA
Sauber's Felipe Nasr lowers the benchmark to a 1:22.750 to knock Nico Rosberg down to second on the timesheets.
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Red Bull on TwitterCopyright: Red Bull on Twitter
Looks like Red Bull have finished work on the car as Daniel Ricciardo is in the cockpit and raring to go. The Australian has only managed five laps today.
Rosberg back on top
PACopyright: PA
Nico Rosberg reaches his century of laps and he pumps in a 1:22.810, the first driver to get down into the 1m22s today, to go fastest. Sauber's Felipe Nasr drops to second, 0.944 seconds adrift.
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After a spot of lunch, Nico Rosberg is back out in the Mercedes. A little over three hours of today's session remain.
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McLaren add: "We can replace those components ahead of running tomorrow. The issue was promptly spotted by Fernando on an out-lap - so quick to trace."
McLaren end day early
It was all going so well for McLaren this morning, but the team say their day is done. "We've had a loss of cooling water pressure & have removed the power unit for inspection," tweet the team. "That's a long process, so it ends today's running."
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Pace-setter Felipe Nasr dives back into the pits, as he approaches the 50-lap mark. That leaves Felipe Massa's Williams out on track with Toro Rosso's Carlos Sainz Jr for company.
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BBCCopyright: BBC
F1 journalist Dan Knutson in Jerez: "Red Bull magnate Dietrich Mateschitz has arrived at the circuit. He and team principal Christian Horner strolled down to the Toro Rosso garage for a chat."
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Getty ImagesCopyright: Getty Images
Felipe Nasr is one of three rookies on the grid this season and arrives in the sport having finished third in the GP2 series, collecting four wins along the way.
The 22-year-old Brazilian gained experience as Williams' test driver in 2014 and lists the 2011 British Formula Three and 2009 Formula BMW Europe titles under his achievements.
Nasr goes quickest
Getty ImagesCopyright: Getty Images
A Sauber goes quickest! Felipe Nasr clocks a 1:24.052, which is 0.022 seconds faster than the Ferrari of Kimi Raikkonen.
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Mercedes report that an engine shutdown brought Nico Rosberg's last run to a halt, adding the crew are looking into it now. After a faultless opening day at this test, a few niggles have started to creep into the world champion's programme.
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Kimi Raikkonen,Felipe Nasr and Felipe Massa are back in the pits, leaving Carlos Sainz Jr and Pastor Maldonado with the track to themselves.
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McLarenCopyright: McLaren
McLaren: Back at a snowy MTC... Tyre warmers needed we reckon.
BreakingHeadlines
Here are the day's headlines:
Kimi Raikkonen sets the pace for Ferrari after track dries in Jerez
Nico Rosberg closes on a tally of 100 laps, but losing time after stopping out on track
McLaren finally get some laps on the board, with Fernando Alonso managing more than 30
Felipe Nasr spins, bringing out the first red flag of the day
Lotus delayed because of telemetry issues
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Ferrari's Kimi Raikkonen improves on his leading lap time with a 1:24.074, 0.696 seconds clear of Mercedes' Nico Rosberg, who is busy having lunch.
Get involved
#bbcf1
Alex Withington: At last some progress for @McLarenF1 We know it's testing but after 4 stop/start/stop days those 32 laps are a huge relief to us fans.
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Honda Racing F1: 32 laps. Always testing, always learning. Lets see what this afternoon brings.
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MercedesCopyright: Mercedes
Mercedes: Pasta, salmon and an engineering debrief - isn't that how everyone takes their lunch? #BackToWork
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Kimi Raikkonen is out and about in the Ferrari, along with the Sauber of Felipe Nasr, who is back in the car after a spot of lunch.
Go! Go! Go!
And we're back under way in Jerez!
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So while we wait for the marshals to retrieve the stricken Mercedes, let's have a recap.
Kimi Raikkonen is quickest with a 1:24.357, 0.413 seconds ahead of Mercedes' Nico Rosberg. Carlos Sainz Jr is third, ahead of Pastor Maldonado, Daniel Ricciardo, Felipe Nasr, Fernando Alonso and Felipe Massa.
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Mercedes: So @nico_rosberg is catching a lift back from T10 it seems: he'd better not be late for lunch. We'll keep you posted on his progress..
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Force IndiaCopyright: Force India
Force India: It seems the whole of F1 is fascinated with the snow at home, so here is a shot of our HQ under a white blanket...
Red flag
We've got our second red flag of the day and this time it is Nico Rosberg's Mercedes which is responsible.
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WilliamsCopyright: Williams
Following snow shots of Red Bull's Milton Keynes base and Mercedes HQ in Brackley, I bring you the outlook over at Grove where Williams are based.
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McLaren report that they have stopped running to grab a spot of lunch. Just over four hours and 20 minutes remain of today's session.
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Fernando Alonso: Encouraging morning here at the test! 32 laps. We keep learning about the car!
Raikkonen sets pace
Kimi Raikkonen dips into the 1m24s with a 1:24.357, four tenths quicker than Mercedes' Nico Rosberg. Nice little tussle at the top of the timesheets between these two, trading lap times over the last hour or so.
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Getty ImagesCopyright: Getty Images
Sauber have stopped for a spot of lunch, with Felipe Nasr currently sixth fastest, 9.254 seconds off the pace. The Brazilian rookie, who had a spin this morning, has completed 30 laps.
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F1 journalist Dan Knutson in Jerez: They are changing the Renault engine in Daniel Ricciardo's Red Bull. He has done only five laps so far today. It's obviously not a routine scheduled change because the team would have done that last night.
"Meanwhile, Fernando Alonso headed off to the McLaren hospitality unit, so his car is out of action for at least a short time. He has now completed 32 laps."
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Why have we seen so little of the Red Bull this morning? Well I have the answer coming up for you...
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SilverstoneCopyright: Silverstone
Earlier, we published an image of a snow-covered Brands Hatch. Over at Silverstone, there's been a dusting of the white stuff, too. It's just as well testing is taking place in southern Spain, eh...
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BBCCopyright: BBC
BBC F1 pit-lane reporter Tom Clarkson: Found Esteban Gutierrez watching - and signing - at the chicane.
BreakingHeadlines
Here are the day's headlines:
Nico Rosberg sets the pace in the Mercedes as the track dries in Jerez
McLaren finally get some laps on the board, with Fernando Alonso managing more than 30
Felipe Nasr spins, bringing out the first red flag of the day
Lotus delayed because of telemetry issues
Rosberg goes quickest
Getty ImagesCopyright: Getty Images
Nico Rosberg back on top now, the Mercedes driver clocking a 1:26.064, with Toro Rosso's Carlos Sainz Jr slotting into second, just 0.003 seconds adrift. Kimi Raikkonen is third now, two tenths off the pace in the Ferrari.
Raikkonen back on top
McLaren's Fernando Alonso heads out for a single lap before heading back to the pits.
Meanwhile, Kimi Raikkonen goes second in the Ferrari with a 1:27.093 and then moves into top spot by breaking into the 1m26s.
The Finn is now two tenths quicker than Nico Rosberg's Mercedes, with Carlos Sainz Jr 1.4 seconds further back.
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And having just said it's been a while since we've seen the Williams,Felipe Massa - an 11-time race winner and the 2008 world championship runner up - pops out for a spin.
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Mercedes' Nico Rosberg improves the benchmark time to a 1:26.746, 1.129 seconds clear of Toro Rosso's Carlos Sainz Jr.
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We've seen very little of the Williams of Felipe Massa and Red Bull's Daniel Ricciardo today. The pair have completed just a handful of laps.
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McLarenCopyright: McLaren
McLaren: Fernando pits after getting some solid laps under his belt. #McLarenHonda is back on the leaderboard. #Jerez
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Getty ImagesCopyright: Getty Images
The times are tumbling with Nico Rosberg improving his leading time to a 1:27.073 with Carlos Sainz Jr popping into second in the Toro Rosso, 0.802 seconds adrift.
Rosberg reclaims top spot
Kimi Raikkonen's time at the top doesn't last long as Nico Rosberg pops in a 1:27.400 to set the fastest time with a little under three hours of the session completed so far.
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Kimi Raikkonen goes quicker still with a 1:28.137 in the Ferrari with Mercedes' Nico Rosberg closing the gap to just 0.082 seconds.
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BBCCopyright: BBC
F1 journalist Dan Knutson in Jerez: "Pastor Maldonado did one lap and then pitted. The left front wing and left side of the Lotus was covered in green flow-vis paint that shows where and how the air is flowing around the car."
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Mercedes' Nico Rosberg pits, takes on the dry tyres and heads back out in an attempt to reclaim top spot on the timesheets.
Raikkonen goes fastest
Ferrari's Kimi Raikkonen goes second with a 1:33.454 and then moves to the summit of the timesheets with a 1:29.228, three seconds clear of Nico Rosberg.
That lap was set on dry tyres, while Rosberg's was on the intermediates. Expect the rest of the field to switch to dry tyres shortly as a dry line emerges.
"Of the teams we know have survived the winter, only Force India were behind Lotus in terms of readiness for the start of testing. Force India have stayed in the UK and are planning only to do the final two Barcelona tests. Lotus, meanwhile, after planning to miss the first two days in Jerez because of delays in preparing the car, managed to get themselves ahead of schedule and Pastor Maldonado did a useful 29 laps on Monday before he was halted by a drivetrain failure.
"He said the car was 'a different car, not a continuation of last year', which is probably no bad thing after Lotus's dire 2014. 'We ran with a lot of fuel, we didn't touch the set-up, but the car seems to be consistent, quite reactive, easy to feel, the sensations are good. It's a good day, a good first day,' the Venezuelan said."
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Good stuff from McLaren and Fernando Alonso at the moment with 27 laps on the board. Only Nico Rosberg and Mercedes have done more on 41.
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Lotus say they have sorted their telemetry issue, with Pastor Maldonado heading out for an installation lap.
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Nico Rosberg sneaks past Fernando Alonso at Turn One after the McLaren driver runs wide.
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McLarenCopyright: McLaren
Jenson Button is wrapped up with a cuppa as he and McLaren racing director Eric Boullier follow Fernando Alonso's progress in the garage.
BreakingHeadlines
Here are the day's headlines:
Nico Rosberg sets the pace in the Mercedes on a damp day in Jerez
McLaren finally get some laps on the board, with Fernando Alonso managing 20
Felipe Nasr spins, bringing out the first red flag of the day
Lotus have yet to run because of telemetry issues
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Kimi Raikkonen goes fifth fastest in the Ferrari, four second off the pace set by Nico Rosberg.
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Red Bull on TwitterCopyright: Red Bull on Twitter
Red Bull: "As the team continue their work in Jerez, the factory has received a bit of a white paint job of its own overnight."
"Fernando Alonso is not exactly setting the timing screens on fire but nevertheless this is a much more encouraging morning so far from the McLaren-Honda. After just two hours, the two-time champion has already completed nearly 20 laps - more than the Honda engine had completed over four previous days in a McLaren at this test and the post-season one in Abu Dhabi. Even once the track dries out, though, don't expect Alonso to start posting quick laps.
"The key for McLaren-Honda this week is to learn how and whether the car works, in terms of reliability rather than performance. As team-mate Jenson Button said on Monday: 'It won't be about set-up work, it'll be putting mileage on it. The important thing is to get our heads down and work through all the systems. We will not be setting the world on fire with lap times or laps on circuit. We are still at zero in terms of understanding our performance."
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Fernando Alonso is clocking up the laps in the McLaren. The Spaniard has managed 16, which is more than was achieved on day one and day two combined. It looks like things are starting to go in the right direction.
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Sauber report that Felipe Nasr went wide in corner eight and ran into the gravel. "No real damage," they add. "The team is getting the car ready again."
"Sauber have been second fastest on both days so far, while both Marcus Ericsson and Felipe Nasr have had a day each in the car. The team are desperately hoping the C34 is a step forward from last year's model, which gave the team the worst season in its history.
"But the car looks noticeably more bulky than some of its rivals and the appearance of both men towards the top of the speed trap times suggests it is running pretty light on fuel. The team, though, are making positive noises, and head of track engineering Giampaolo Dall'Ara says they 'seem to have a good basis to work from'."
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MercedesCopyright: Mercedes
Mercedes: Meanwhile, back in Brackley... can we just stay @circuitodejerez until the next test @Circuitcat_eng [Circuit Catalunya in Barcelona] please?! #Brrr
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We've not seen the Lotus yet and here's why: "Still chasing a pesky telemetry issue this morning, Cliff Richard playing, hopefully out soon," tweet the team.
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Fernando Alonso is back out in the McLaren, along with Mercedes' Nico Rosberg and Toro Rosso's Carlos Sainz Jr.
Go! Go! Go!
And we're go, go, go again in Jerez!
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The Sauber is back in the pits, which means the session should get under way again shortly.
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Mercedes: RADIO: "What are we waiting for?!" Someone's keen...
Get involved
#bbcf1
James Grimwood: McLaren's woes don't worry me. Red Bull were in a similar position last year and ended up winning races.
Justin Regan: If Red Bull can get close to matching top speeds then we have a competition on our hands. Both Dan's have proven they have the talent.
David Tyrrell: McLaren may not be doing loads of laps but it's better to work out the problems than skip over them.
"Felipe Massa takes over the Williams on Tuesday after two quietly successful and productive days' work by team-mate Valtteri Bottas. It's early, of course, but the signs are Williams have had a solid winter and built nicely on the foundations of 2014, when they leapt back up to the front of the field, arresting a decade of decline. 'We've had zero problems with the car and there is a good feeling,' Bottas said."
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We're still under red flag conditions as we wait for marshals to recover the stricken Sauber.
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McLaren: "Some laps already under our belt this morning - feels like progress."
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The Sauber driver spun and is now in the gravel. A recovery truck is on its way...
Red flag
Oh. That run comes to an abrupt end as Sauber's Felipe Nasr has brought out the red flag. Woops.
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And it's a third run for McLaren! A third run!
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Getty ImagesCopyright: Getty Images
Just Felipe Nasr's Sauber and the Toro Rosso of Carlos Sainz Jr out on track at the moment.
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Mercedes: Overnight dampness just about starting to clear on track - @nico_rosberg goes for the slick look :)
"Monday was not a good day for Red Bull. Daniil Kvyat went off on an out lap early in the morning and damaged the front wing mounting pillars. There were no spares, so the team were forced to run without a front wing for the rest of the day, which meant only systems checks were possible.
"A slightly chastened Kvyat admitted: 'These things happen and they happened to me at the wrong moment. I was going very slowly but sometimes it is not even enough. Many factors. You don't spin many times on the out lap. One of the smallest incidents I had but one of the most costly ones.'"
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BBCCopyright: BBC
F1 journalist Dan Knutson in Jerez: "As you can see from this photo from Monday, the Ferrari guys are using eight screens on wheels to hide the new car as it comes into the pits. They set up the screens on three sides, and then as soon as the driver pulls into the slot the mechanics quickly pull two of the screens around and completely enclose the car.
"Given that the Ferrari was the quickest car on the first two days of the test, perhaps the team has something worth hiding, although it's worth pointing out that they employed the same tactics in testing last year, too."
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PACopyright: PA
Fernando Alonso takes his count to 10 laps before diving back into the pits. The lap times are nothing to write home about, but the Spaniard has now completed two runs in the McLaren and almost matched the tally he and team-mate Jenson Button achieved over the last two days combined.
Is this the day McLaren's 2015 season finally kicks into gear?
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Fernando Alonso has headed out for a second run of the day in the McLaren, and again, he manages to do more than one lap. Progress at last!
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Catch up on day two's action with this highlights video, which features an interview with world champion Lewis Hamilton.
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Joe Jameson: More F1 testing today! Here's hoping that McLaren have a better day of it...
"After a quite remarkable 157 laps by Nico Rosberg on the first day of testing for Mercedes, Lewis Hamilton experienced the team's first reliability hiccup on Monday with a water leak caused by a failed part. But it was a measure of the rate at which Mercedes have been knocking out the laps that Hamilton had already done 97 laps by the time the car stopped in the pit lane early in the afternoon session.
"'I got in a good amount of laps,' Hamilton said. 'I got a good feel for the car, back in quite quickly, so overall it was good.' He added that the car felt 'very similar to last year really, which is a good thing', but with more downforce. The year has started well for Mercedes, for whom Rosberg is back in the car on Tuesday."
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Kimi Raikkonen breaks the silence as he heads out in the Ferrari. The Finn is joined by the two Felipes - Massa and Nasr in the Williams and Sauber respectively.
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Getty ImagesCopyright: Getty Images
Red Bull have their wing back today, after Daniil Kvyat damaged the only one they had yesterday. A new one was flown in, but that meant Kvyat's running was severely hampered.
Daniel Ricciardo is in the car today and mentioning him means another excuse for us to use an image of their epic camouflage livery.
Get involved
#bbcf1 or 81111 (UK only)
Still quiet on track. I suspect the teams are waiting for the track to dry out. So in the meantime, let's use this lull in the action to get some F1-related chat going.
Do you think McLaren can turnaround their fortunes? Have Mercedes already got this season tied up? Will Red Bull and Ferrari get closer?
Tweet us using the #bbcf1 hashtag or text 81111 (UK only). The floor is yours.
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We've seen every car apart from the Lotus (and Force India who aren't here, obviously) this morning, but the track has now fallen silent.
Approximately 0.2 mm of rain fell in the 20 minutes leading up to the start of testing this morning, so rain tyres have been the order of the day so far.
"Leaving aside McLaren's problems, Sebastian Vettel and Ferrari have grabbed the headlines so far in testing, with the fastest time on both the first two days. Vettel, who hands over to new father Kimi Raikkonen today, was given a round of applause by the Ferrari pit crew after returning to the pits at the end of the day, and joked that they were just pleased he hadn't damaged the car in the damp conditions.
"Vettel says he has been encouraged by progress so far. 'It is still very early to tell because it depends on how you compare to other people,' the four-time world champion said. 'Mercedes are doing extreme long runs, and in that regard it is difficult. I am quite happy with the feeling inside the car and I think we have a good platform to work from.'"
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PACopyright: PA
Kimi Raikkonen heads out with an aerodynamic device strapped to the Ferrari for his early runs. The Finn is taking over from Sebastian Vettel, who spent the first two days in the car.
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PACopyright: PA
Nico Rosberg is out early setting the pace, the Mercedes driver leading the way with a 1:33.058, 1.7 seconds clear of Daniel Ricciardo's Red Bull.
It's been a pretty busy opening half an hour already, with Carlos Sainz Jr, Felipe Nasr, Fernando Alonso and Felipe Massa also posting times.
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McLaren's Fernando Alonso completes two successive laps to put a time on the board - a 1:42.304 which is seven seconds off the pace. Still, it's a lap.
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Laura StevensCopyright: Laura Stevens
The conditions are far from ideal in Jerez, with the track damp and greasy. But that's nothing compared to what it's like over at the legendary Brands Hatch in snow-hit Kent.
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MercedesCopyright: Mercedes
Nico Rosberg is the first man out on track, with Kimi Raikkonen, Daniel Ricciardo and Fernando Alonso joining him. Yes, you read that right, Alonso in the McLaren is out on track. How long that lasts is anyone's guess.
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Nico Rosberg is back behind the wheel of the Mercedes today, with Daniel Ricciardo making a return for Red Bull.
Felipe Massa gets his first taste of the new Williams, while Fernando Alonso is back in at McLaren.
Kimi Raikkonen takes over from Sebastian Vettel at Ferrari, Carlos Sainz Jr is testing the Toro Rosso, Romain Grosjean gets a go in the Lotus and Felipe Nasr is in action for Sauber.
Only Force India are not at this test, after deciding to concentrate on the final two Barcelona tests.
"It's all eyes on McLaren on Tuesday morning. After two days in which Fernando Alonso and Jenson Button have managed just 12 laps between them because of a recurring control-systems issue on the Honda engine, it is time the team got some serious work done. Button and McLaren both said on Monday evening that they felt they had found the problem, and they are about to find out whether they are right.
"Despite the trying start to the programme - remember this comes after they completed just five laps in two days with a 2014 test car fitted with the Honda in Abu Dhabi last November - so far, they have stayed resolutely positive.
"'We've had a few little niggly problems, control issues but we feel the last run was good and we've solved them so hopefully the last two days will be much better,' Button said. 'The packaging and how tight the bodywork is and temperatures; all that stuff is working really well.
"'But if you've only done six laps that's what people see. I'm sure we'll have more problems over the next couple of days - these engines are so complicated - I just hope we can do a bit of running and get a bit of data back to the factory and see where we are and where we need to improve.' Alonso is back in the car on Tuesday."
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APCopyright: AP
There's no point reading into headline times because we don't know the spec in which each team is running their car, nor do we know fuel loads.
But Ferrari and Sebastian Vettel will still be pleased with their efforts so far as the German finished top of the pile on both days and racked up a solid amount of laps.
It's been pretty positive for Mercedes, too, aside from a water leak which curtailed Lewis Hamilton's running yesterday. Still, the team have completed nearly 250 laps - significantly more than anyone else - in two days.
It hasn't gone so well for McLaren, though.
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It is considerably warmer this morning than on the first two days of the test, with the air temperature hovering around 10.4C and the track temperature 9.4C.
Today's session has just got under way and will run until 16:00 GMT. That's eight hours for the teams to continue putting their 2015 challengers through their paces and iron out any issues as the new season approaches.
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ReutersCopyright: Reuters
Hello all and a warm welcome to our live text commentary of day three of pre-season testing in Jerez, southern Spain. We've had two days of testing already but the good news is that there is still two more to go!
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Morning! Who fancies a bit of Formula 1 testing, then?
Live Reporting
Lawrence Barretto
All times stated are UK
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BBCCopyright: BBC - McLaren end day early because of power unit problems, but they managed 32 laps
- Felipe Nasr sets the pace for Sauber after track dries in Jerez
- Nico Rosberg clocks 120 laps, but loses time after stopping out on track
- Nasr spins, bringing out the first red flag of the day
- Lotus delayed because of telemetry issues
- Red Bull endure tough day with limited mileage after engine change

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McLarenCopyright: McLaren - Kimi Raikkonen sets the pace for Ferrari after track dries in Jerez
- Nico Rosberg closes on a tally of 100 laps, but losing time after stopping out on track
- McLaren finally get some laps on the board, with Fernando Alonso managing more than 30
- Felipe Nasr spins, bringing out the first red flag of the day
- Lotus delayed because of telemetry issues

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BBCCopyright: BBC - Nico Rosberg sets the pace in the Mercedes as the track dries in Jerez
- McLaren finally get some laps on the board, with Fernando Alonso managing more than 30
- Felipe Nasr spins, bringing out the first red flag of the day
- Lotus delayed because of telemetry issues

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McLarenCopyright: McLaren - Nico Rosberg sets the pace in the Mercedes on a damp day in Jerez
- McLaren finally get some laps on the board, with Fernando Alonso managing 20
- Felipe Nasr spins, bringing out the first red flag of the day
- Lotus have yet to run because of telemetry issues

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Latest PostPost update
And that's a wrap. Thanks for your company and hope to see you tomorrow when we can do it all over again before waving goodbye to Jerez for another year. Until then, it's good afternoon from me. Adios!
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Lewis Hamilton will swap his bike for the Mercedes W06 tomorrow for the final day of this first test in Jerez. Jenson Button will be in action, too, as will Romain Grosjean, who will get his first go behind the wheel of the new Lotus.
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So an encouraging day for McLaren, albeit it one which was curtailed because of an engine issue. Mercedes will be pleased with another 150 laps in the bag, which brings Nico Rosberg's lap total this week to an staggering 308.
Sauber and Toro Rosso managed more than 100 laps, too, while Ferrari and Lotus almost made the century. It was less successful for Red Bull who missed much of the day before a late flurry of laps from Daniel Ricciardo.
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Mercedes: That's a wrap for @nico_rosberg @circuitodejerez! Nice touch on his in-lap radio: "Thank you everyone - really top job to start to the year".
Day three results
1) Felipe Nasr (Sauber) 1:21.545 108 laps
2) Kimi Raikkonen (Ferrari) 1:21.750 92 laps
3) Nico Rosberg (Mercedes) 1:21.982 151 laps
4) Felipe Massa (Williams) 1:22.276 71 laps
5) Pastor Maldonado (Lotus) 1:22.713 96 laps
6) Carlos Sainz Jr (Toro Rosso) 1:23.187 136 laps
7) Daniel Ricciardo (Red Bull) 1:23.901 48 laps
8) Fernando Alonso (McLaren) 1:35.553 32 laps
Chequered flag
Felipe Nasr finishes fastest on day three of pre-season testing in Jerez.
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Can you guess who is responsible? Yep, it's Pastor Maldonado, whose Lotus has rolled to a halt.
Red flag
With one minute to go, we have a red flag!
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Still no signs of any improvements at this stage, with Pastor Maldonado completing his final run before handing the car over to Romain Grosjean, who has yet to drive the car, for the last day of the test.
Ten minutes to go
It's busy out on track with seven drivers circulating - Nico Rosberg, Daniel Ricciardo, Kimi Raikkonen, Felipe Massa, Felipe Nasr, Pastro Maldonado and Carlos Sainz Jr. Ten minutes to go.
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Fernando Alonso and McLaren have completed the fewest laps of anybody today with 32, with Red Bull's Daniel Ricciardo only having achieved fractionally more at 35 so far. At the other end of the spectrum, Nico Rosberg is up to 145 laps, with Carlos Sainz Jr next up on 124.
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F1 journalist Dan Knutson in Jerez: "Pit stop practice during a long run of laps by Nico Rosberg. The Mercedes W06 is covered in green flow-vis paint, so the mechanics will have lots of cleanup to do tonight."
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Sauber: Felipe Nasr is still on top of the time sheet, now on a longer run.
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Kimi Raikkonen has been joined by Felipe Nasr, Nico Rosberg and Pastor Maldonado as we approach the end of the session. No one coming close to beating the benchmark time set by Nasr.
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F1 journalist Dan Knutson in Jerez: "Kimi Raikkonen is doing a long run. A Ferrari crew member showed him a pit board indicating 15 laps to go."
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Kimi Raikkonen has the track to himself with 40 minutes remaining. The Finn has managed over 70 laps, today. Only Nico Rosberg and Carlos Sainz Jr have crossed the century mark.
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F1 journalist Dan Knutson in Jerez: "The Sauber crew didn't bother putting the usual screens, so here's a shot of the fastest driver and car at the moment - Felipe Nasr and the Sauber - in the garage."
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Mercedes: @nico_rosberg departs the garage with an almighty sneeze for another run...
One hour to go
Just 60 minutes remaining of today's session, with Felipe Nasr heading the timesheets, two tenths clear of Kimi Raikkonen's Ferrari.
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Daniel Ricciardo pops into the pits and then heads straight back out. It looks like the Red Bull might finally get a decent run of laps under its belt before the day is out.
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Pastor Maldonado is still out there, along with Carlos Sainz Jr, Felipe Massa and Daniel Ricciardo.
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Fernando Alonso: Big step forward... #McLarenHonda #proud #Progress
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F1 journalist Dan Knutson in Jerez: "Work has been going on behind the screens in the Red Bull garage for most of the day.
"With Daniil Kvyat doing 18 laps yesterday and Daniel Ricciardo doing just 12 so far today, it really has been a couple of wasted days for the team as far as getting mileage on the car is concerned."
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Pastor Maldonado goes fourth quickest for Lotus with a 1:22.950, 1.4 seconds off the pace set by Felipe Nasr in the Sauber.
BreakingHeadlines
Here are the day's headlines:
Listen to the McLaren-Honda
Want to know what the new McLaren-Honda sounds like? Thought you would. Click here to hear a comparison between that and the Mercedes.
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Hurrah, Ferrari fire up their car and send Kimi Raikkonen on his way, with Nico Rosberg and Felipe Massa following him down the pit lane.
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The track falls silent.
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Red Bull: Hitting all the notes, just not necessarily in the right order... That's testing!
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Lotus are having an encouraging day with Pastor Maldonado passing his half century of laps before heading back to the pits for a few tweaks to the car.
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Williams: Felipe reports the track is improving as he completes an eight lap run, taking his total to 47 for the day.
Two hours to go
With two hours to go, Felipe Nasr heads the timesheets with a 1:21.545, 0.8 seconds clear of Kimi Raikkonen's Ferrari. Mercedes' Nico Rosberg is third, four tenths adrift.
Felipe Massa is fourth, ahead of Daniel Ricciardo, Pastor Maldonado, Carlos Sainz Jr and Fernando Alonso.
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F1 journalist Dan Knutson in Jerez: "Like the rest of the teams, Williams plan to put a number of upgrades on their car. Williams will run their Australian Grand Prix spec car, or something very close to that version, at the last pre-season test.
"'We are going to see changes between now and Melbourne,' chief technical officer Pat Symonds said. 'You will see them in the final days of the final Barcelona test.'"
Nasr back on top
But back comes Felipe Nasr, the Sauber driver clocking a 1:21.545 to bump Kimi Raikkonen down to second. We shouldn't read anything into this really, as we don't know what fuel loads they're running while different tyre compounds will also have an affect, too.
Raikkonen goes quickest
It's straight down to business for Ferrari's Kimi Raikkonen as the Finn pumps in a 1:22.351 which sends him flying to the top of the timesheets.
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Break over at Ferrari as Kimi Raikkonen heads back out on track, with Williams' Felipe Massa and Sauber's Felipe Nasr for company.
Recap
Nico Rosberg's Mercedes spent some time on the back of a truck earlier today when the engine broke down during the German's run.
Nasr reclaims top spot
Sauber's Felipe Nasr lowers the benchmark to a 1:22.750 to knock Nico Rosberg down to second on the timesheets.
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Looks like Red Bull have finished work on the car as Daniel Ricciardo is in the cockpit and raring to go. The Australian has only managed five laps today.
Rosberg back on top
Nico Rosberg reaches his century of laps and he pumps in a 1:22.810, the first driver to get down into the 1m22s today, to go fastest. Sauber's Felipe Nasr drops to second, 0.944 seconds adrift.
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After a spot of lunch, Nico Rosberg is back out in the Mercedes. A little over three hours of today's session remain.
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McLaren add: "We can replace those components ahead of running tomorrow. The issue was promptly spotted by Fernando on an out-lap - so quick to trace."
McLaren end day early
It was all going so well for McLaren this morning, but the team say their day is done. "We've had a loss of cooling water pressure & have removed the power unit for inspection," tweet the team. "That's a long process, so it ends today's running."
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Pace-setter Felipe Nasr dives back into the pits, as he approaches the 50-lap mark. That leaves Felipe Massa's Williams out on track with Toro Rosso's Carlos Sainz Jr for company.
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F1 journalist Dan Knutson in Jerez: "Red Bull magnate Dietrich Mateschitz has arrived at the circuit. He and team principal Christian Horner strolled down to the Toro Rosso garage for a chat."
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Felipe Nasr is one of three rookies on the grid this season and arrives in the sport having finished third in the GP2 series, collecting four wins along the way.
The 22-year-old Brazilian gained experience as Williams' test driver in 2014 and lists the 2011 British Formula Three and 2009 Formula BMW Europe titles under his achievements.
Nasr goes quickest
A Sauber goes quickest! Felipe Nasr clocks a 1:24.052, which is 0.022 seconds faster than the Ferrari of Kimi Raikkonen.
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Mercedes report that an engine shutdown brought Nico Rosberg's last run to a halt, adding the crew are looking into it now. After a faultless opening day at this test, a few niggles have started to creep into the world champion's programme.
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Kimi Raikkonen,Felipe Nasr and Felipe Massa are back in the pits, leaving Carlos Sainz Jr and Pastor Maldonado with the track to themselves.
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McLaren: Back at a snowy MTC... Tyre warmers needed we reckon.
BreakingHeadlines
Here are the day's headlines:
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Ferrari's Kimi Raikkonen improves on his leading lap time with a 1:24.074, 0.696 seconds clear of Mercedes' Nico Rosberg, who is busy having lunch.
Get involved
#bbcf1
Alex Withington: At last some progress for @McLarenF1 We know it's testing but after 4 stop/start/stop days those 32 laps are a huge relief to us fans.
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Honda Racing F1: 32 laps. Always testing, always learning. Lets see what this afternoon brings.
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Mercedes: Pasta, salmon and an engineering debrief - isn't that how everyone takes their lunch? #BackToWork
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Kimi Raikkonen is out and about in the Ferrari, along with the Sauber of Felipe Nasr, who is back in the car after a spot of lunch.
Go! Go! Go!
And we're back under way in Jerez!
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So while we wait for the marshals to retrieve the stricken Mercedes, let's have a recap.
Kimi Raikkonen is quickest with a 1:24.357, 0.413 seconds ahead of Mercedes' Nico Rosberg. Carlos Sainz Jr is third, ahead of Pastor Maldonado, Daniel Ricciardo, Felipe Nasr, Fernando Alonso and Felipe Massa.
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Mercedes: So @nico_rosberg is catching a lift back from T10 it seems: he'd better not be late for lunch. We'll keep you posted on his progress..
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Force India: It seems the whole of F1 is fascinated with the snow at home, so here is a shot of our HQ under a white blanket...
Red flag
We've got our second red flag of the day and this time it is Nico Rosberg's Mercedes which is responsible.
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Following snow shots of Red Bull's Milton Keynes base and Mercedes HQ in Brackley, I bring you the outlook over at Grove where Williams are based.
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McLaren report that they have stopped running to grab a spot of lunch. Just over four hours and 20 minutes remain of today's session.
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Fernando Alonso: Encouraging morning here at the test! 32 laps. We keep learning about the car!
Raikkonen sets pace
Kimi Raikkonen dips into the 1m24s with a 1:24.357, four tenths quicker than Mercedes' Nico Rosberg. Nice little tussle at the top of the timesheets between these two, trading lap times over the last hour or so.
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Sauber have stopped for a spot of lunch, with Felipe Nasr currently sixth fastest, 9.254 seconds off the pace. The Brazilian rookie, who had a spin this morning, has completed 30 laps.
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F1 journalist Dan Knutson in Jerez: They are changing the Renault engine in Daniel Ricciardo's Red Bull. He has done only five laps so far today. It's obviously not a routine scheduled change because the team would have done that last night.
"Meanwhile, Fernando Alonso headed off to the McLaren hospitality unit, so his car is out of action for at least a short time. He has now completed 32 laps."
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Why have we seen so little of the Red Bull this morning? Well I have the answer coming up for you...
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Earlier, we published an image of a snow-covered Brands Hatch. Over at Silverstone, there's been a dusting of the white stuff, too. It's just as well testing is taking place in southern Spain, eh...
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BBC F1 pit-lane reporter Tom Clarkson: Found Esteban Gutierrez watching - and signing - at the chicane.
BreakingHeadlines
Here are the day's headlines:
Rosberg goes quickest
Nico Rosberg back on top now, the Mercedes driver clocking a 1:26.064, with Toro Rosso's Carlos Sainz Jr slotting into second, just 0.003 seconds adrift. Kimi Raikkonen is third now, two tenths off the pace in the Ferrari.
Raikkonen back on top
McLaren's Fernando Alonso heads out for a single lap before heading back to the pits.
Meanwhile, Kimi Raikkonen goes second in the Ferrari with a 1:27.093 and then moves into top spot by breaking into the 1m26s.
The Finn is now two tenths quicker than Nico Rosberg's Mercedes, with Carlos Sainz Jr 1.4 seconds further back.
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And having just said it's been a while since we've seen the Williams,Felipe Massa - an 11-time race winner and the 2008 world championship runner up - pops out for a spin.
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Mercedes' Nico Rosberg improves the benchmark time to a 1:26.746, 1.129 seconds clear of Toro Rosso's Carlos Sainz Jr.
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We've seen very little of the Williams of Felipe Massa and Red Bull's Daniel Ricciardo today. The pair have completed just a handful of laps.
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McLaren: Fernando pits after getting some solid laps under his belt. #McLarenHonda is back on the leaderboard. #Jerez
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The times are tumbling with Nico Rosberg improving his leading time to a 1:27.073 with Carlos Sainz Jr popping into second in the Toro Rosso, 0.802 seconds adrift.
Rosberg reclaims top spot
Kimi Raikkonen's time at the top doesn't last long as Nico Rosberg pops in a 1:27.400 to set the fastest time with a little under three hours of the session completed so far.
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Kimi Raikkonen goes quicker still with a 1:28.137 in the Ferrari with Mercedes' Nico Rosberg closing the gap to just 0.082 seconds.
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F1 journalist Dan Knutson in Jerez: "Pastor Maldonado did one lap and then pitted. The left front wing and left side of the Lotus was covered in green flow-vis paint that shows where and how the air is flowing around the car."
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Mercedes' Nico Rosberg pits, takes on the dry tyres and heads back out in an attempt to reclaim top spot on the timesheets.
Raikkonen goes fastest
Ferrari's Kimi Raikkonen goes second with a 1:33.454 and then moves to the summit of the timesheets with a 1:29.228, three seconds clear of Nico Rosberg.
That lap was set on dry tyres, while Rosberg's was on the intermediates. Expect the rest of the field to switch to dry tyres shortly as a dry line emerges.
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Andrew Benson
Chief F1 writer
"Of the teams we know have survived the winter, only Force India were behind Lotus in terms of readiness for the start of testing. Force India have stayed in the UK and are planning only to do the final two Barcelona tests. Lotus, meanwhile, after planning to miss the first two days in Jerez because of delays in preparing the car, managed to get themselves ahead of schedule and Pastor Maldonado did a useful 29 laps on Monday before he was halted by a drivetrain failure.
"He said the car was 'a different car, not a continuation of last year', which is probably no bad thing after Lotus's dire 2014. 'We ran with a lot of fuel, we didn't touch the set-up, but the car seems to be consistent, quite reactive, easy to feel, the sensations are good. It's a good day, a good first day,' the Venezuelan said."
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Good stuff from McLaren and Fernando Alonso at the moment with 27 laps on the board. Only Nico Rosberg and Mercedes have done more on 41.
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Lotus say they have sorted their telemetry issue, with Pastor Maldonado heading out for an installation lap.
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Nico Rosberg sneaks past Fernando Alonso at Turn One after the McLaren driver runs wide.
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Jenson Button is wrapped up with a cuppa as he and McLaren racing director Eric Boullier follow Fernando Alonso's progress in the garage.
BreakingHeadlines
Here are the day's headlines:
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Kimi Raikkonen goes fifth fastest in the Ferrari, four second off the pace set by Nico Rosberg.
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Red Bull: "As the team continue their work in Jerez, the factory has received a bit of a white paint job of its own overnight."
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Andrew Benson
Chief F1 writer
"Fernando Alonso is not exactly setting the timing screens on fire but nevertheless this is a much more encouraging morning so far from the McLaren-Honda. After just two hours, the two-time champion has already completed nearly 20 laps - more than the Honda engine had completed over four previous days in a McLaren at this test and the post-season one in Abu Dhabi. Even once the track dries out, though, don't expect Alonso to start posting quick laps.
"The key for McLaren-Honda this week is to learn how and whether the car works, in terms of reliability rather than performance. As team-mate Jenson Button said on Monday: 'It won't be about set-up work, it'll be putting mileage on it. The important thing is to get our heads down and work through all the systems. We will not be setting the world on fire with lap times or laps on circuit. We are still at zero in terms of understanding our performance."
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Fernando Alonso is clocking up the laps in the McLaren. The Spaniard has managed 16, which is more than was achieved on day one and day two combined. It looks like things are starting to go in the right direction.
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Sauber report that Felipe Nasr went wide in corner eight and ran into the gravel. "No real damage," they add. "The team is getting the car ready again."
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Andrew Benson
Chief F1 writer
"Sauber have been second fastest on both days so far, while both Marcus Ericsson and Felipe Nasr have had a day each in the car. The team are desperately hoping the C34 is a step forward from last year's model, which gave the team the worst season in its history.
"But the car looks noticeably more bulky than some of its rivals and the appearance of both men towards the top of the speed trap times suggests it is running pretty light on fuel. The team, though, are making positive noises, and head of track engineering Giampaolo Dall'Ara says they 'seem to have a good basis to work from'."
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Mercedes: Meanwhile, back in Brackley... can we just stay @circuitodejerez until the next test @Circuitcat_eng [Circuit Catalunya in Barcelona] please?! #Brrr
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We've not seen the Lotus yet and here's why: "Still chasing a pesky telemetry issue this morning, Cliff Richard playing, hopefully out soon," tweet the team.
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Fernando Alonso is back out in the McLaren, along with Mercedes' Nico Rosberg and Toro Rosso's Carlos Sainz Jr.
Go! Go! Go!
And we're go, go, go again in Jerez!
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The Sauber is back in the pits, which means the session should get under way again shortly.
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Mercedes: RADIO: "What are we waiting for?!" Someone's keen...
Get involved
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James Grimwood: McLaren's woes don't worry me. Red Bull were in a similar position last year and ended up winning races.
Justin Regan: If Red Bull can get close to matching top speeds then we have a competition on our hands. Both Dan's have proven they have the talent.
David Tyrrell: McLaren may not be doing loads of laps but it's better to work out the problems than skip over them.
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Andrew Benson
Chief F1 writer
"Felipe Massa takes over the Williams on Tuesday after two quietly successful and productive days' work by team-mate Valtteri Bottas. It's early, of course, but the signs are Williams have had a solid winter and built nicely on the foundations of 2014, when they leapt back up to the front of the field, arresting a decade of decline. 'We've had zero problems with the car and there is a good feeling,' Bottas said."
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We're still under red flag conditions as we wait for marshals to recover the stricken Sauber.
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McLaren: "Some laps already under our belt this morning - feels like progress."
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The Sauber driver spun and is now in the gravel. A recovery truck is on its way...
Red flag
Oh. That run comes to an abrupt end as Sauber's Felipe Nasr has brought out the red flag. Woops.
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And it's a third run for McLaren! A third run!
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Just Felipe Nasr's Sauber and the Toro Rosso of Carlos Sainz Jr out on track at the moment.
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Mercedes: Overnight dampness just about starting to clear on track - @nico_rosberg goes for the slick look :)
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Andrew Benson
Chief F1 writer
"Monday was not a good day for Red Bull. Daniil Kvyat went off on an out lap early in the morning and damaged the front wing mounting pillars. There were no spares, so the team were forced to run without a front wing for the rest of the day, which meant only systems checks were possible.
"A slightly chastened Kvyat admitted: 'These things happen and they happened to me at the wrong moment. I was going very slowly but sometimes it is not even enough. Many factors. You don't spin many times on the out lap. One of the smallest incidents I had but one of the most costly ones.'"
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F1 journalist Dan Knutson in Jerez: "As you can see from this photo from Monday, the Ferrari guys are using eight screens on wheels to hide the new car as it comes into the pits. They set up the screens on three sides, and then as soon as the driver pulls into the slot the mechanics quickly pull two of the screens around and completely enclose the car.
"Given that the Ferrari was the quickest car on the first two days of the test, perhaps the team has something worth hiding, although it's worth pointing out that they employed the same tactics in testing last year, too."
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Fernando Alonso takes his count to 10 laps before diving back into the pits. The lap times are nothing to write home about, but the Spaniard has now completed two runs in the McLaren and almost matched the tally he and team-mate Jenson Button achieved over the last two days combined.
Is this the day McLaren's 2015 season finally kicks into gear?
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Fernando Alonso has headed out for a second run of the day in the McLaren, and again, he manages to do more than one lap. Progress at last!
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Catch up on day two's action with this highlights video, which features an interview with world champion Lewis Hamilton.
Get involved
#bbcf1
Joe Jameson: More F1 testing today! Here's hoping that McLaren have a better day of it...
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Andrew Benson
Chief F1 writer
"After a quite remarkable 157 laps by Nico Rosberg on the first day of testing for Mercedes, Lewis Hamilton experienced the team's first reliability hiccup on Monday with a water leak caused by a failed part. But it was a measure of the rate at which Mercedes have been knocking out the laps that Hamilton had already done 97 laps by the time the car stopped in the pit lane early in the afternoon session.
"'I got in a good amount of laps,' Hamilton said. 'I got a good feel for the car, back in quite quickly, so overall it was good.' He added that the car felt 'very similar to last year really, which is a good thing', but with more downforce. The year has started well for Mercedes, for whom Rosberg is back in the car on Tuesday."
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Kimi Raikkonen breaks the silence as he heads out in the Ferrari. The Finn is joined by the two Felipes - Massa and Nasr in the Williams and Sauber respectively.
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Red Bull have their wing back today, after Daniil Kvyat damaged the only one they had yesterday. A new one was flown in, but that meant Kvyat's running was severely hampered.
Daniel Ricciardo is in the car today and mentioning him means another excuse for us to use an image of their epic camouflage livery.
Get involved
#bbcf1 or 81111 (UK only)
Still quiet on track. I suspect the teams are waiting for the track to dry out. So in the meantime, let's use this lull in the action to get some F1-related chat going.
Do you think McLaren can turnaround their fortunes? Have Mercedes already got this season tied up? Will Red Bull and Ferrari get closer?
Tweet us using the #bbcf1 hashtag or text 81111 (UK only). The floor is yours.
Post update
We've seen every car apart from the Lotus (and Force India who aren't here, obviously) this morning, but the track has now fallen silent.
Approximately 0.2 mm of rain fell in the 20 minutes leading up to the start of testing this morning, so rain tyres have been the order of the day so far.
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Andrew Benson
Chief F1 writer
"Leaving aside McLaren's problems, Sebastian Vettel and Ferrari have grabbed the headlines so far in testing, with the fastest time on both the first two days. Vettel, who hands over to new father Kimi Raikkonen today, was given a round of applause by the Ferrari pit crew after returning to the pits at the end of the day, and joked that they were just pleased he hadn't damaged the car in the damp conditions.
"Vettel says he has been encouraged by progress so far. 'It is still very early to tell because it depends on how you compare to other people,' the four-time world champion said. 'Mercedes are doing extreme long runs, and in that regard it is difficult. I am quite happy with the feeling inside the car and I think we have a good platform to work from.'"
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Kimi Raikkonen heads out with an aerodynamic device strapped to the Ferrari for his early runs. The Finn is taking over from Sebastian Vettel, who spent the first two days in the car.
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Nico Rosberg is out early setting the pace, the Mercedes driver leading the way with a 1:33.058, 1.7 seconds clear of Daniel Ricciardo's Red Bull.
It's been a pretty busy opening half an hour already, with Carlos Sainz Jr, Felipe Nasr, Fernando Alonso and Felipe Massa also posting times.
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McLaren's Fernando Alonso completes two successive laps to put a time on the board - a 1:42.304 which is seven seconds off the pace. Still, it's a lap.
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The conditions are far from ideal in Jerez, with the track damp and greasy. But that's nothing compared to what it's like over at the legendary Brands Hatch in snow-hit Kent.
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Nico Rosberg is the first man out on track, with Kimi Raikkonen, Daniel Ricciardo and Fernando Alonso joining him. Yes, you read that right, Alonso in the McLaren is out on track. How long that lasts is anyone's guess.
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Nico Rosberg is back behind the wheel of the Mercedes today, with Daniel Ricciardo making a return for Red Bull.
Felipe Massa gets his first taste of the new Williams, while Fernando Alonso is back in at McLaren.
Kimi Raikkonen takes over from Sebastian Vettel at Ferrari, Carlos Sainz Jr is testing the Toro Rosso, Romain Grosjean gets a go in the Lotus and Felipe Nasr is in action for Sauber.
Only Force India are not at this test, after deciding to concentrate on the final two Barcelona tests.
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Andrew Benson
Chief F1 writer
"It's all eyes on McLaren on Tuesday morning. After two days in which Fernando Alonso and Jenson Button have managed just 12 laps between them because of a recurring control-systems issue on the Honda engine, it is time the team got some serious work done. Button and McLaren both said on Monday evening that they felt they had found the problem, and they are about to find out whether they are right.
"Despite the trying start to the programme - remember this comes after they completed just five laps in two days with a 2014 test car fitted with the Honda in Abu Dhabi last November - so far, they have stayed resolutely positive.
"'We've had a few little niggly problems, control issues but we feel the last run was good and we've solved them so hopefully the last two days will be much better,' Button said. 'The packaging and how tight the bodywork is and temperatures; all that stuff is working really well.
"'But if you've only done six laps that's what people see. I'm sure we'll have more problems over the next couple of days - these engines are so complicated - I just hope we can do a bit of running and get a bit of data back to the factory and see where we are and where we need to improve.' Alonso is back in the car on Tuesday."
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There's no point reading into headline times because we don't know the spec in which each team is running their car, nor do we know fuel loads.
But Ferrari and Sebastian Vettel will still be pleased with their efforts so far as the German finished top of the pile on both days and racked up a solid amount of laps.
It's been pretty positive for Mercedes, too, aside from a water leak which curtailed Lewis Hamilton's running yesterday. Still, the team have completed nearly 250 laps - significantly more than anyone else - in two days.
It hasn't gone so well for McLaren, though.
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It is considerably warmer this morning than on the first two days of the test, with the air temperature hovering around 10.4C and the track temperature 9.4C.
Today's session has just got under way and will run until 16:00 GMT. That's eight hours for the teams to continue putting their 2015 challengers through their paces and iron out any issues as the new season approaches.
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Hello all and a warm welcome to our live text commentary of day three of pre-season testing in Jerez, southern Spain. We've had two days of testing already but the good news is that there is still two more to go!
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Morning! Who fancies a bit of Formula 1 testing, then?