The Wallabies will be without three players for their clash with Argentina after being hit by injuries in their victory over South Africa last weekend.
Matt Giteau has been the latest player to be ruled out of this week's Rugby Championship Test in Argentina with a sternum injury picked up against the Springboks.
The news follows the loss of Will Genia and Rob Horne to injuries, with the Wallabies forced to call in reinforcements for their trip to South America.
Chest scans cleared Toulon-based Giteau of any serious damage after Saturday's game against the Springboks but team officials said they have opted to rest the 32-year-old for the next stage of the tournament.
"I know how desperate Matthew was to play and continue to contribute to this group over the next week, his leadership and presence off the field will be missed," Wallabies coach Michael Cheika said.
"It's disappointing to lose him for this round. However, knowing he will be right to go for the Bledisloe series (against New Zealand) is reassuring for the group and our fans.
"In the end, the decision sits with me. It's going to be a big year for Gits and to send him over to Mendoza after a very physical Test as well as a tight turnaround, just isn't fair on him or the group."
The exclusion of Giteau from the 31-man squad to Mendoza makes way for the return of ACT Brumbies playmaker Christian Leali'ifano, who is back after being used as an additional training squad member only in the lead-up to the Springboks Test.
"For the Wallabies to be successful, we need to have the belief that our depth can cover each position and I have that confidence in Christian if he's called upon for this weekend's match," added Cheika.
Nick Cummins and Nic White were also added to the squad on Sunday following the injuries to Genia and Horne.
There were two further additions in hooker James Hanson and prop Tetera Faulkner, following Australia's last-gasp 24-20 victory in Brisbane on the weekend.
- AAP