The Wallabies have suffered a major blow in the lead-up to their must-win Rugby Championship clash with South Africa in Perth on Saturday night, with Stephen Moore ruled out of what would have been a record-breaking Test for the veteran hooker.
Moore suffered a low grade strain in his right hamstring at Wallabies training on Thursday, with scans confirming he will miss at least this match against the Springboks.
The Brumbies No.2 was set to surpass Jeremy Paul as the most capped Australian hooker of all time, but must now wait to write his name into the history books with a 73rd appearance for his country.
Tatafu Polota-Nau has been called into the starting line-up, in a reverse of what happened before Australia's last-start loss to New Zealand - when Moore was promoted for the injured NSW hooker.
Queensland rake Saia Fainga'a once again comes into the squad on the bench as the Wallabies look to overcome yet another injury setback.
Australia, who are fighting to remain the world No.2 side, must beat the Springboks to maintain their ranking and alleviate pressure on under-siege coach Robbie Deans.
Victory is their only hope of keeping their slim Rugby Championship ambitions alive.
Prop Ben Alexander says Moore's omission wouldn't disrupt the Wallabies preparations.
"No, we've been practising a lot at training with lots of different combinations, we very rarely pack more than a couple in a row with the same guys," said Alexander.
"We're always changing props, changing sides, changing hookers, so it shouldn't cause any problem.
"We all know what (Polota-Nau) is capable of."
Meanwhile, Wallabies players say they're taking responsibility for the pressure being heaped on Deans, but insist they won't use speculation surrounding the coach's future as motivation for the remainder of the Rugby Championship.
There are rumblings that Deans' contract may be prematurely ended if the Wallabies continue to struggle in the Championship, after Australia slumped to a tenth straight Bledisloe Cup series defeat with back-to-back losses to the All Blacks.
Prop Alexander denied rumour surrounding Deans' job security would be a factor in Saturday's clash with South Africa in Perth, but made it clear the playing group were rallying behind their coach.
"That criticism of Robbie, it hurts us too because it's how we played and a reflection of us and how we represented our country, and we didn't do a great job," said Alexander on Thursday.
"We feel a responsibility for the side not performing ... (but) as far as all that speculation goes, it's not a focus of ours.
"Our focus is just going out, playing well and representing our country with pride."
Alexander admitted the Wallabies were taught some harsh lessons by the All Blacks and said the team was determined to give Australian supporters the performance they deserved against the Springboks.
"We got stood up by the best side in the world and we've copped that on the chin and we've looked back and they exposed us everywhere," Alexander said.
"Now we get a chance to right those wrongs."