Israel Folau is set to make a surprise comeback but prop Taniela Tupou is racing the clock after being included in a 31-strong Wallabies squad for the Rugby Championship clashes against South Africa and Argentina.
Folau is a chance of overcoming an ankle injury, which sidelined him for Australia's heavy second Test loss to the All Blacks in Auckland, and run out against the Springboks in Brisbane on Saturday night. The other clash against the Pumas will be played on the Gold Coast on September 15.
It is a surprise return for Folau who was expected to be sidelined for at least a month when he limped off in the Bledisloe Cup Test in Sydney a fortnight ago.
"I have spoken to him a few times and he is doing well and in high spirits, hopefully he is right to go," Wallabies back-rower Lukhan Tui said of Folau.
Tui was also keeping his fingers crossed prop Tupou - dubbed the Tongan Thor - would overcome a hamstring complaint that forced him to miss Australia's two heavy losses to the All Blacks.
"Whatever team he plays in he will make a big impact," Tui said of Tupou. "He is a game-changing player. Almost a one of a kind player."
Tupou backed himself to not only play but start for besieged coach Michael Cheika against the Springboks at Suncorp Stadium. Tupou damaged his hamstring before the Bledisloe Cup opener.
"If Cheika wants me to start definitely it's something I have been looking forward to," Tupou said.
The squad for the two Tests features three new faces - Brumbies Player of the Year Rory Arnold and Queensland pair Brandon Paenga-Amosa and Caleb Timu.
Hooker Paenga-Amosa featured in all three Tests of Australia's 2-1 series loss to Ireland in June while Timu is in fine form after a try for Queensland Country in Saturday's National Rugby Championship clash with Canberra Vikings.
The Wallabies - last on the Rugby Championship table - are desperate to bounce back to form with wins on home soil. They have lost six of their past seven Tests including back-to-back defeats to the All Blacks that have put coach Michael Cheika's future under the microscope.
Wallabies squad: Forwards: Allan Alaalatoa, Rory Arnold, Adam Coleman, Folau Fainga'a, Ned Hanigan, Michael Hooper (capt), Sekope Kepu, Tolu Latu, Brandon Paenga-Amosa, David Pocock, Tatafu Polota-Nau, Tom Robertson, Izack Rodda, Pete Samu, Rob Simmons, Scott Sio, Caleb Timu, Lukhan Tui, Taniela Tupou. Backs: Tom Banks, Kurtley Beale, Israel Folau, Bernard Foley, Will Genia, Dane Haylett-Petty, Reece Hodge, Marika Koroibete, Jack Maddocks, Nick Phipps, Joe Powell, Matt Toomua.