George Smith
George Smith will play in his final Test for Australia against the British and Irish Lions on Saturday. [Reuters]

George Smith has insisted that Saturday's deciding Test against the British and Irish Lions will be the final appearance in an extraordinary international career that has seen him win 110 caps for Australia.

The flanker has been selected ahead of Michael Cooper in Australia's only change to their starting XV as they look to secure a memorable series victory over the Lions in Sydney this weekend.

Australia coach Robbie Deans was hoping to convince the 32 year old to continue his Test career in order to compete in the upcoming Rugby Championship, but Smith has made it clear that this will be a one-off cameo.

"I'm pretty sure this will be the last game I play for Australia. No, it will be!" declared Smith. "I've had a fantastic international career and know when to bow out. The legacy I've left behind on the international stage I'm very proud of. This just caps it off.

"I retired in 2009 in Wales and played away from home with not too many friends and family there watching. This gives me the opportunity to play in front of them and to play in front of an Australian crowd on home soil.

"It will be fitting for my career to look back on and say 'I've finished on a great occasion, a big moment. In terms of rugby it's the ultimate for me. To be selected in the starting XV for this decider, there's nothing higher for me."

Deans confirmed that he had asked Smith to continue his international career, perhaps partly due to David Pocock missing the remainder of the season because of a serious knee injury.

"I've encouraged George never to retire! I did put the question of his future to him in training today. His response was not dissimilar, but I didn't take any heed of it. I dismissed it," said Deans.

Smith will hope that he can help inspire Australia to victory on Saturday in what would be a fitting end to an international career that has spanned more than 13 years.