Matt Giteau's role in Australia's World Cup challenge has been clouded by his omission from the Wallabies' squad to play South Africa on Saturday, while the stocks of Brumbies teammate Pat McCabe continue to soar.

Giteau, who started at five-eighth in Sunday's upset loss to Samoa, couldn't get a start in his other regular spot of inside centre or even on the bench with Quade Cooper coming in at pivot and Pat McCabe staying in the No.12 jersey.

Several frontliners who didn't play against Samoa were recalled including halfback Will Genia, fullback Kurtley Beale, winger and goalkicker James O'Connor and openside flanker David Pocock.

Giteau, who will play with French club Toulon after the World Cup, was a near-permanent fixture in the starting side until recently.

However, the 92-Test veteran ended last year against France on the bench behind Berrick Barnes at inside centre and Cooper at five-eighth.

Coach Robbie Deans was characteristically cagey when asked about how Giteau's omission would impact on his World Cup prospects and if he still had a big part to play in the team.

"Gits is part of the squad so he has a big role to play. We prepare as one and next week is another week," Deans said.

"We're presuming nothing going forward. If you look at the way things have unfolded, you just can't presume anything.

"Matt will obviously want a role going forward. He has a role going forward. We don't know exactly what that will entail as yet in terms of playing, that will unfold."

McCabe, 23, has made just two Test appearances and played most of his rugby for the Brumbies out wide, although he also had some time in the centres.

Deans said McCabe did well against Samoa and had the potential to be a regular Test centre.

"He's well suited to the midfield. He's played most of the football on the edge, whether it be wing or fullback," Deans said.

"He's got speed and he's also got size and he's a good decision maker."

Giteau aside, the other stalwart missing from the run-on side to play the Springboks is lock Nathan Sharpe.

Sharpe and debutant Sitaleki Timani were replaced by the Queensland duo of James Horwill and Rob Simmons.

"They (Horwill and Simmons) are fresh. It's a short turnaround, so they have that benefit. They also have the advantage of being a combination in recent times," Deans said.

Deans dismissed the suggestion South Africa was understrength, despite leaving many of their star players at home due to fitness concerns, and said he expected a lot from the Springboks.

"It's not an understrength side. They've been preparing and are very focused."

Happy with the versatility in his backline, Deans was comfortable with having five forwards on his bench.

Wallabies team: Kurtley Beale, James O'Connor, Adam Ashley-Cooper, Pat McCabe, Digby Ioane, Quade Cooper, Will Genia, Ben McCalman, David Pocock, Rocky Elsom (capt), James Horwill, Rob Simmons, Ben Alexander, Stephen Moore, Sekope Kepu. Res: Saia Faingaa, Pekahou Cowan, Nathan Sharpe, Matt Hodgson, Scott Higginbotham, Nick Phipps, Anthony Faingaa.

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