Lynchpin fly-half Stephen Larkham is certain to miss Australia's November Test against Ireland, as well as their tour outings against England and Wales, due to a shoulder injury.
The 31-year-old ACT Brumbies star, who started all three of the Wallabies' recent outings against South Africa, had an MRI scan on his return home from last weekend's Tri-Nations opener against the Springboks.
The findings now suggest Larkham needs a six-month lay-off to boot, including a full shoulder reconstruction.
Australia's autumn tour itinerary includes a Twickenham date against England on November 12, followed, seven days later, by a clash with Ireland at Lansdowne Road, with a finish against Six Nations champions Wales in Cardiff on November 26.
"The shoulder itself didn't feel that bad on Saturday, but the MRI indicates it is, and the advice is to have the reconstruction now," said Larkham.
"It is a tough decision, but the right thing to do to give me the best opportunity in time to recover for next year.
"It's disappointing on a number of fronts, missing out on the rest of the Test season, the upcoming Bledisloe Cup match against the All Blacks and the opportunity to improve on our start to the Tri-Nations."
Matt Giteau and Elton Flatley are likely to come into contention for Larkham's position throughout the remainder of the Tri-Nations and the autumn tour.
Meanwhile, the following is the 27-man squad Australia coach Eddie Jones has named for Saturday week's Bledisloe Cup clash with the All Blacks:
Al Baxter, Brendan Cannon, Mark Chisholm, Matt Dunning, Rocky Elsom, Scott Fava, Elton Flatley, Mark Gerrard, Matt Giteau, George Gregan (Capt), Nic Henderson, Chris Latham, David Lyons, Drew Mitchell, Stephen Moore, Stirling Mortlock, Jeremy Paul, Clyde Rathbone, John Roe, Nathan Sharpe, George Smith, Lote Tuqiri, Morgan Turinui, Dan Vickerman, Phil Waugh, Chris Whitaker, Bill Young.