The Wallabies have resisted the temptation to fire barbs at rivals England ahead of a pool of death clash at Twickenham on Saturday (Sunday morning AEST).

England captain Chris Robshaw has been hammered for his decision to turn down a late penalty shot at goal for a chance to draw to instead go for an attacking lineout in a 28-25 loss to Wales last weekend.

Had England scored a try, Robshaw would have been a hero.

But he is dealing with the fallout as his team sits on the cusp of an embarrassing exit from the World Cup before the quarter-finals.

Moore said Cheika had empowered him to "back myself" when the game is on the line.

"As a captain you make that call when you see it and you do what you think is best to win the game," Moore said.

"Every captain would do that in that situation. Whether it comes off or not, there's all sorts of things involved. But you make the call and go for it.

"I suppose as a captain, that's what I try to do.

"Cheik has been great in terms of telling me, 'mate, just back yourself in those situations'.

"That gives me a lot of confidence, there's no wrong option there. You just have a go."

Moore was in Robshaw's shoes in a Test against South Africa in July, where the Wallabies trailed by three points with time running out.

He turned down a penalty opportunity and was rewarded when outside centre Tevita Kuridrani barged over for a match-winning try

"If it doesn't come off you look like a mug. You do what you think is best at the time and he obviously did that so there's no cut-and-dried formula for that situation," Moore said.

"You do what you think is best for your team. I suppose that is part of being a captain.

"You live and die by your decisions. As a leader, you put a lot of preparation into those moments and do what is best for your team.

"Whatever happens, happens. That is where the cards fall. That is one of the great things about rugby, that unpredictability."

Moore admitted the Wallabies were rocked when news broke that Skelton (pectoral) and Palu (hamstring) would miss the rest of the World Cup with injuries.

The pair will return to Australia in the coming days and have already had their World Cup accreditation taken off them.

They have been replaced by Sam Carter and James Hanson in the 31-man squad.

Moore joked that prop Scott Sio would sleep easy knowing he no longer has to act as the back-up hooker, with Hanson's arrival bolstering the rake stocks.

"I guess the biggest hole [with injuries] is the emotional part," Moore said.

"You really feel for those guys and to bow out during the World Cup, and the amount of work these guys have done to get to this position, you really feel for them.

"But you have to move on, don't you? That's the nature of it. I think it's important to acknowledge the guys that are leaving us and what they have contributed.

"I guess it gives us a little bit of motivation now to keep doing it for those guys, who haven't got the opportunity to play any more."

The Wallabies are in the thick of the World Cup build-up at their hotel in the centre of London and their plush training venue at an exclusive private school.

But they are refusing to be drawn on England's predicament and the fact the hosts are in danger of being knocked out of contention.

The Wallabies could conceivably lose to England, but still make it through to the next stage of the tournament.