The Wallabies have suffered a double blow with rookie centre David Feliuai pulling out of their camp and veteran Kurtley Beale undergoing surgery after rupturing an Achilles tendon.
Ahead of their opening Test match against Wales on Saturday in Sydney, NSW Waratahs centre Joey Walton has been called into the squad.
Utility back Beale suffered the injury playing club rugby in Sydney, which likely spells the end of the 35-year-old's international career after 95 Tests.
He went for scans on Monday which confirmed his worst fears.
Feliuai, who made a name for himself with Melbourne Rebels this Super Rugby Pacific season, withdrew for personal reasons.
Coach Joe Schmidt will on Thursday name his first Test team since taking over from World Cup failure Eddie Jones.
The second Wales match is at Melbourne's AAMI Park on July 13, followed by a one-off Test against Georgia in Sydney on July 20.
Australia A representative Walton won't feature at Allianz Stadium this week but Schmidt's first-choice centre pairing is far from clear.
There are reports Brumbies ace Len Ikitau has a hamstring injury.
The outside centre was at a Wallabies fan day in Sydney on Sunday, with his teammate Andrew Kellaway unaware of any injury news.
The two leading outside-centre options against Wales are Queensland's Josh Flook and Filipo Daugunu, who has rejoined the Reds from the Melbourne Rebels.
Flook already has an established Reds partnership with inside centre Hunter Paisami which could give him the edge given the team's short preparation for the first Test of the year.
Making a name for himself as a winger, Daugunu spent time at No.13 with the Rebels, earning himself the club's Players' Player award for the 2024 season.
Kellaway can also play outside centre but is more likely to feature on the wing or at fullback.
Playing his seventh and last Test at the end of 2021 Daugunu said he was happy to line up anywhere in the backline.
"I've been away for two years so I tried really hard to be back again and I'm happy to be here," the 29-year-old said.
"It was a good chance for me when I went to Melbourne to play more at 13 so I can try to crack the Wallabies again."
He said he'd improved his fitness and his game knowledge since his last opportunity.
"I just tried to understand more about rugby and improve myself week after week so I’m happy to be here.
“It’s tough to play international (rugby) and to play you need to be fit and understand the whole game plan and your role in the team."