SYDNEY, July 20 (Reuters) - Matt Giteau will miss Australia's second Rugby Championship test against Argentina because of a chest injury he sustained on his return from international exile at the weekend.
The 32-year-old centre, who played his first test in four years in Saturday's 24-20 victory over South Africa, will be replaced in the squad for the match against the Pumas at Mendoza by Christian Lealiifano.
Scans on nose and sternum injuries after the match in Brisbane cleared Giteau of serious injury but coach Michael Cheika chose not to take him to Argentina when the squad flew out of Sydney on Monday.
"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," Cheika said.
"He's one of the toughest members in the squad and we all witnessed during the match just how passionate Matthew is about representing his country again.
"It's disappointing to lose him for this round, however knowing he will be right to go for the Bledisloe series 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."
Cheika had already indicated he would make some changes to his team for Saturday's match and Matt Toomua looks likely to get a start at inside centre after impressing when he came off the bench against the Springboks.
Australia play New Zealand in the first of two Bledisloe Cup tests in Sydney on Aug. 8, with the second match, which is not part of the Rugby Championship, taking place in Auckland the following week.
Scrumhalf Will Genia (knee) and winger Rob Horne (calf) had already been ruled out of the trip to Argentina and will be replaced in the squad by Nic White and Nick Cummins respectively.
Revised squad:
Forwards - James Slipper, Scott Sio, Greg Holmes, Sekope Kepu, Stephen Moore, Tatafu Polota-Nau, James Hanson, Rob Simmons, Will Skelton, James Horwill, Dean Mumm, Scott Fardy, Scott Higginbotham, Ben McCalman, Sean McMahon, Michael Hooper, David Pocock.
Backs - Nick Phipps, Nic White, Bernard Foley, Quade Cooper, Matt Toomua, Christian Lealiifano, Kurtley Beale, Tevita Kuridrani, Adam Ashley-Cooper, Drew Mitchell, Joe Tomane, Nick Cummins, Israel Folau.