Australia cannot afford to contemplate anything other than victory in the third Test at Perth with a grassy wicket likely to produce a result that could seal the hosts' Ashes fate, captain Ricky Ponting said on Wednesday.

Australia trail the five-Test series 1-0 after suffering a crushing innings and 71-run loss in Adelaide.

A win for England in the third Test, starting on Thursday, would hand the tourists their first Ashes triumph on Australian soil in 24 years and condemn Ponting to become the first Australian skipper in more than 120 years to lose the Ashes three times.

"Looking at the wicket you'd think that there's going to be result in this game, so obviously that has to be a positive one for us or it's game, set and match," Ponting told reporters after training at the WACA ground.

"We're applying ourselves to play our best game, our best game so far in the series, and we know we have to do that by a long way if we want to win the game.

"I'm pretty confident with the group of players that we've got together and the way we've trained over the last few days that we can do that over the next five days," he added.

While he was certain the pitch would prove pivotal in the series, its conditions were forcing selectors to hedge their bets as to whether to play a spinner or bring a four-pronged pace attack.

"It's not the thicker coarse grass that was on the wicket here the last couple of years, it's a sort of finer, leaf sort of grass. When you've got wickets like that the ball tends to skip off the grass a bit more rather than holding as much.

"With a bit of grass on the wicket there's every chance the ball will stay newer for longer than it probably does in most other places as well so you'd think it's going to swing a bit more," Ponting said added.

Australia's selectors shook up the side that slumped in Adelaide, dropping Marcus North for two-Test all rounder Steven Smith and recalling dropped pace duo Ben Hilfenhaus and Mitchell Johnson at the expense of Doug Bollinger in a 12-man squad.

Phillip Hughes, who was bullied out of the Australian side by England's seamers during the losing series last year, will replace injured opener Simon Katich.

Untried left-arm spinner Michael Beer was the biggest shock selection in the squad, beating Nathan Hauritz as a candidate to exploit turn on a wearing pitch late in the Test.

Local pundits and former players have raged against selectors and the team's performances, but Ponting said England had their own headaches.

England lost Stuart Broad to an abdomen injury after Adelaide, while fellow paceman James Anderson had his preparations cut short to attend the birth of his child.

"We've all done those flights in the past and it takes a couple of days to get over them but we'll see how (Anderson) pulls up," said Ponting, who was mindful of England's abysmal record on the traditionally quick pitches at the WACA.

"I honestly feel that the pitch conditions here are as foreign to English players as probably anywhere else in the world and hopefully we can exploit that this week," he added.

Ponting will turn 36 on Sunday, the fourth day of the test, and has endured mounting speculation over his captaincy.

While he said he had not given any thought to the captaincy question he conceded the result in Perth could take the issue out of his hands.

I'll do my best to make sure we're on a winning end this week, I'll do my best to make sure I score runs and leave the team in the best way possible and then the powers that be will make that decision after the series or after this test match," he said.