McLaren's Lewis Hamilton says he has no realistic hopes of being on pole position for the Abu Dhabi Grand Prix despite promising practice pace.
Hamilton was fastest in first practice and 0.168 seconds behind Red Bull's Sebastian Vettel in the second.
But asked if he had a chance of pole, Hamilton said: "Honestly, no. But I'm going to give it my all.
"The last four races have been won by a certain guy. But if we get ahead it will be a huge bonus."
Vettel has won the last four races to move 13-points clear of title rival Fernando Alonso in the world championship.
Alonso's Ferrari was sixth fastest in second practice, 0.836secs behind Vettel, after trying out a series of new parts aimed at closing the gap to the Red Bull.
Hamilton said that he had been happy with his car in first practice but not in the second and that he suspected he was failing to get the 'soft' 'option' tyres into their correct working temperature range.
"It's been an interesting day. We have got through quite a lot. It seemed quite good in P1. P2 was a bit of a struggle for me.
"I set a good time on the prime ['medium' compound tyre] but people seemed to find about 0.8secs on the option and I wasn't able to get any time out of it. Perhaps it's about switching the tyres on.
"If we get pole it would be fantastic but we shouldn't get our hopes up; Sebastian has got a faster car."
Team-mate Jenson Button was third fastest, 0.661secs behind Vettel, but pointed out that McLaren's pace on race-simulation runs was competitive.
In fact, the McLaren drivers were marginally faster than Vettel during their long runs, and the Ferrari drivers also appeared to be competitive on race pace.
Button said: "The car is working reasonably well. The long run is promising, the car feels good, not too bad.
"For us trying to get the tyres working in three laps is key. [With] low fuel there are areas to work on, and getting the tyres in the right working range is part of that.
"Long run, the balance feels reasonably good. Trying to understand the tyres, how hard you can push them on the long run and degradation you don't know until you've started.
"It was fun to drive the car, there are areas to improve but we know what to do.
"Our qualifying pace as a team has been very good most of the year. The last few races the Red Bulls have been a lot quicker which has helped them but their race pace has always been very strong.
"If we can be as quick or quicker than the Red Bulls on race pace that is as important or more important than qualifying in front of them."
Alonso made no comment about his car's performance but Ferrari technical director Pat Fry said "some" of the new parts tried "seem to be positive".