This weekend's third Test with Wales was supposed to be the 34-year-old's Wallaby swansong before hanging up his boots for good after the Force's last Super 15 fixture against the Crusaders on July 14.
Injury to Australia skipper James Horwill has now altered that initial plan, with head coach Robbie Deans persuading Sharpe to answer an SOS call for the newly-extended Rugby Championship.
Sharpe will now stay on for the Tests against New Zealand, South Africa and Argentina before retiring in early October.
"Sharpey's indicated he's willing and keen to continue into the Rugby Championship, so that's good news for the group," said Deans, who lost Horwill to a hamstring injury last month and is unsure whether fellow second row Dan Vickerman will ever fully recover from a chronic leg problem.
"Obviously it is a big decision for Sharpey because it was a conscious choice of his to communicate that he was going to retire, intending to retire, and that's a big decision in any man's life, particularly a bloke who's played 100 Tests.
"So he's made plans around his life beyond the game and he's had to put them on hold and that's never straightforward.
"He's been preparing for this moment for some time which is a good thing and a great example to young players, so he's deferred that and that's a significant commitment from him."
Sharpe's decision to carry on for the short-term at least raises hopes that he may yet be convinced that next year's Lions tour is within his grasp.
The highly-respected star has insisted he has no plans to continue indefinitely but Deans was coy when asked whether he would be attempting to persuade Sharpe to stay on until next summer.
"It won't be happening…is the initial indication," added Deans, who left media wondering if he might just be making a similar announcement beyond October.