'Leadership key for England now it's win or go home'

Rugby World Cup quarter-final: England v Australia
Venue: Oita Stadium Date: Saturday, 19 October Kick-off: 08:15 BST
Coverage: Live commentary on BBC Radio 5 Live and online with text updates on the BBC Sport website and app.

I think England coach Eddie Jones' decision to move Owen Farrell to fly-half for Saturday's quarter-final against Australia is the right one.

In fact, so long as Henry Slade was fit to replace him in the centres, I think it was inevitable.

I feel for George Ford, who has started every match of this World Cup at 10, because he has played really well in Japan - but maybe his previous form in the big matches has counted against him.

In the handful of huge pressure games at international level in his career he has maybe slightly wobbled.

It might be a bit harsh on him because he is further down the line and more confident now. But certainly in the past when he has played in knock-out games with big decisions, I would not have necessarily said he would be my first pick.

Owen Farrell and Henry Slade — Slade (right) has made just two replacement appearances since the draw with Scotland in March

Farrell, with Manu Tuilagi and Slade outside him was a good combination during the Six Nations.

It is a combination that the opposition struggled to get any change out of in defence, and which was very threatening in attack.

It shuts down a lot of options for the opposition in terms of where they can attack because Farrell is so solid there - they have got to come up with something different.

But there is going to be a question mark over Slade, who has not played more than 40 minutes of rugby since May because of a knee injury. Will he be sharp enough?

Certainly during the Six Nations he was on a bit of a run. He looked very dangerous going forward. He ran great supporting lines, showed great skill and feet - kicking as well as running.

Defensively, he read the play brilliantly - so I like that combination.

Expect the unexpected from Wallabies

Australia are going to come out with something that England have not seen before and will not expect.

It is a big shout putting 19-year-old Jordan Petaia, who only has two caps, in at centre. But at least it is his favoured position - rather than the wing, where he has won his previous caps - so it is not like they are entirely throwing him in at the deep end.

England's focus will be on Petaia, so you can guarantee that Australia are thinking about going somewhere else and playing in a different way so that England will have to tweak their defence.

They are a very clever bunch and England need to be very open-minded about what Australia can bring.

The one surprise for me in Australia's selection for Saturday is Will Genia playing at nine, because I don't think he's been on great form. I think Nic White has been more solid as a starter and Genia has come on when the game is open.

If I was in that England side I would be thinking, there's the guy we will squeeze. They need to try and put pressure on the ruck so that Genia gets static ball and becomes a bit indecisive. I think England will embrace that scrum-half selection.

In addition, Genia and fly-half Christian Lealiifano have only started together once before. Compared to Ben Youngs and Farrell, there is a huge difference there.

Chance for Underhill and Curry to become stars

In the back row, Australia will want to make sure the experience of David Pocock and captain Michael Hooper gives them an advantage over England flankers Sam Underhill and Tom Curry.

But it could just ignite Underhill and Curry to be the stars of this World Cup. If they get it right against Pocock and Hooper, who are up there as the best in the world as a partnership, the England boys are going to put their name in lights.

Michael Hooper and David Pocock are two breakdown specialists who could derail England's campaign

Pocock and Hooper will be well aware that their reputation is up for grabs and this game is going to get all their focus and then some.

In all of these quarter-finals you are going to get every last ounce of effort and experience - everything is going to be thrown out there. Nothing will be left to chance.

When you have built up to it for four years, nothing else matters. There are no warm-up games, there is no qualification from the pool. This is it. This is why they sacrificed themselves, why they have been playing for as long as they have and what they dreamt of from when they were at school.

You have got Pocock and Hooper who have been around the block, played some big games, but never won a World Cup. It will be their last chance.

Then you have got the young pretenders coming through who were probably inspired by Pocock and Hooper and now want to take their mantle.

Is there a leader of the pack for England?

The question hanging over England's performances has always been, can they win the game if they are behind with 20 minutes to go?

Of course, I would prefer England not to be in that position. But it could come down to the leadership within the team. You have got Farrell as captain, but who is the pack leader? It is not easy to say. If you ask eight people they would probably name eight different players.

When it comes to pressure moments, one voice in the forwards has to make things happen.

There are plenty of players with 50 or more caps. They should be, by now, good enough at making those decisions.

It is whether they do it in a quarter-final of the World Cup when there is no tomorrow, no debrief. It is win and move on or go home.

Matt Dawson was speaking to BBC Sport's Becky Grey.