|Rugby World Cup|
|Hosts: England Dates: 18 September-31 October|
|Coverage: Live on BBC Radio 5 live and sports extra, plus live text commentary on every match on the BBC Sport website.|
|Further coverage: BBC Radio Wales, BBC Radio Cymru, BBC Radio Scotland, BBC Radio Ulster and BBC Local Radio.|
It was another compelling weekend of World Cup action, with Scotland and Samoa serving up a thriller, but my favourite matches over the weekend were the two battles to finish top of their pools
Wales against Australia and Ireland versus France were ferocious, savage games.
They were brutal and gladiatorial and you could feel how much was on the line for all four teams - coming second wasn't an option and it was great to watch.
The mighty Irish
Ireland beat France to reach the quarter-finals, and they were unbelievably brilliant in the second half.
They won despite losing Johnny Sexton, Paul O'Connell and Peter O'Mahony, and it shows how much belief head coach Joe Schmidt has instilled in this team that they can go on and deliver without those leaders on the pitch.
Sean O'Brien summed it up in his post-match interview when he said, and I'm paraphrasing here, "it was sad that the lads got injured but the games keep coming and we have to get on with it".
They dealt with it, the other players stepped up and they got on with it.
Ian Madigan, who came on at fly-half for the Irish, has a very different game in his head to that of Sexton because of their different skill sets.
Sexton is very experienced and seems to like detail and organisation - he does not like to play off the cuff too much - whereas I don't think Madigan is a process player, he is more instinctive.
However, one similarity would be their goal-kicking, because at provincial level Madigan had an 87% kicking success rate for Leinster last season, which is top class.
Madigan might be more instinctive in his approach but has the skill set to implement a Schmidt playbook, because otherwise I don't think the coach would have him in the squad.
If Sexton doesn't play against Argentina, Madigan will have to temper his urge to run with the ball and make sure he executes the kicking strategies accurately, which will take a lot of concentration.
You simply can't replace players like O'Connell and Sexton like-for-like because of how much they are involved in running the team on the field - a different voice just won't be the same.
The replacements have to play as big as the O'Connells and Sextons so at least the practical element to the team performance isn't missed.
Lock Iain Henderson is playing some superb rugby so his impact will be positive, and after Madigan came on and played so well he, Schmidt and the team will be confident he can raise his game again.
O'Brien will be missed if he's banned for the incident with Pascal Pape. He's such a destructive runner, there's no one in the Irish back row that will have a similar impact.
Someone can replace him and achieve as many turnovers, but he'll definitely be missed in attack when it comes to carrying the ball.
Ireland's quarter-final opponents, Argentina, have been very good, going about their business to great effect. Their opening game against New Zealand was fantastic.
The Pumas have so far scored 22 tries but conceded seven, while the Irish have only scored 16 but perhaps more importantly only conceded two.
Ireland should see themselves into the semis if they execute their game plan as well as they did to get past France.
However, the Pumas have had good wins against top-ranked sides recently and are capable of winning this game on a good day.
Wales must work on taking chances
The scoreline for Australia's win over Wales reflects the intensity of the respective defences at work in this game.
The clearest thing to come out of the game - and shown most by the period when Australia had two men in the sin-bin - is that Wales needed more composure to finish off the try-scoring situations they created.
Wales will review this match and realise more calmness at important times will provide better decision-making, as we saw from them against England.
Wales's task against South Africa in the quarter-finals is huge; another gigantic game for a team that have been running at maximum capacity for their last three matches.
After that stunning early loss to Japan, the Boks are now up and running - they have found their mojo and will be looking to unload a whole lot of pain on this battered Welsh squad.
Wales have been heroic in getting this far and I hope they find yet more courage within themselves to summon up another peak performance, otherwise this game could be massively one-sided in South Africa's favour.
Wales do have the ability to win this game - a lot of their players have been here before and got the job done against the Boks - and although it's a big shout to find that energy, they just have to.
Wales's massive injury list illustrates how important it is to have big, competitive squads.
The bench players have to play their parts for a team to be successful, it's so crucial these guys come on and up the tempo with positive impact.
In my day you were lucky to get on because no one wanted to come off to give the reserves a chance of playing well and taking your place in the next game.
|Wales's injured players|
|Leigh Halfpenny, full-back (knee)||Rhys Webb, scrum-half (foot)|
|Jonathan Davies, centre (knee)||Scott Williams, centre (knee)|
|Cory Allen, centre (hamstring)||Hallam Amos, wing (shoulder)|
|Liam Williams, wing/full-back (foot)||Eli Walker, wing (hamstring)|
|Rhodri Jones, prop (arm)|
If you were taken off the pitch back in the day it was seen that you hadn't played well but that's not the case now - you actually have 40-60 minute players, it's the way it is in the modern game.
The game is very physical at times but players are conditioned for it, or they should be. Injuries are generally caused accidentally and conditioning is so scientific these days they shouldn't get it wrong.
In the main Wales's best players have done their jobs well so far this tournament and newbies like scrum-half Gareth Davies have lifted their personal performance bar very high.
I doubt very much head coach Warren Gatland will move away from his experienced back trio of Dan Lydiate, Sam Warburton and Taulupe Faletau for the Boks. It would be a big tactical shift this late in the day and that trio has served Gatland and the team well in the past.
Scotland need to raise their game
For me, Scotland's tactics were wrong in the game against Samoa. Yes they won, but it was harder than it should have been.
Keeping the ball in hand and in play was right up Samoa's street and they capitalised on Scotland's craziness.
Scotland can very well turn round and say it was a tactic to tire the Samoans out - and if it was it did indeed work - but they cut it very fine.
Scotland's normally very good defence was exposed but the Scottish hadn't had to deal with runners like the explosive and powerful Samoans before, and they were playing at their scintillating best.
They are unpredictable and Australia in the last eight will run more familiar lines - not that that makes them any easier to beat.
It's a shame for Samoa that they left their best rugby until the last game. I think the off-field challenges currently going on within their country's rugby structure may have had a bigger impact on the squad than they imagined they would.
Scotland captain Greig Laidlaw has led his team well from scrum-half. He's steady, gets to the breakdown quickly, delivers a decent ball to the first receiver, kicks his box-kicks out of hand well and is very accurate when kicking for points off the tee.
He uses his speed of thought well to make up for what he misses in foot speed.
Farrell is not an inside centre
England ran in 10 tries against Uruguay to finish off the tournament with a modicum of pride but you can't compare the new-look backline to the ones that played in the pool games that mattered.
Having said that, the new backline did a decent job considering the difficult week's build up they must have had.
For me a Ford/Farrell combination at fly-half and inside centre just isn't dynamic enough, there are far better centres playing week in, week out than Farrell.
Owen is a very good fly-half and that's where he should always play for England.
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