Israel Folau has been passed fit for Australia's Rugby World Cup Pool A decider against Wales on Saturday and Sean McMahon replaces the suspended Michael Hooper in a side that includes three changes.

Folau was a doubt for this weekend's clash at Twickenham after sustaining an ankle injury in the victory over England last Saturday, but the full-back has recovered in time to face Warren Gatland's men.

McMahon is preferred to Ben McCalman in the absence of Hooper, who was banned for one match for clearing Mike Brown at a ruck in the 33-13 win against England.

Rob Horne misses out due to the shoulder injury he suffered in that match, so Drew Mitchell replaces him on the wing and lock Dean Mumm starts in place of Rob Simmons, who has been named among the replacements.

With Hooper sidelined, head coach Michael Cheika has named Pocock and Adam Ashley-Cooper as vice-captains for a clash which will decide which team will finish top.

Australia only need to avoid defeat to ensure they win Pool A and face Scotland or Japan in the quarter-finals, with the runner-up facing a last-eight showdown against South Africa.

Cheika said: "Every match in this tournament has required our team to step up to another level and we'll need to do that again against an undefeated Welsh team.

"Every player in our squad knows the improvements required, and we still have two days to continue to make them, both individually and as a team.

"Saturday night at Twickenham is another opportunity for us to put in a solid performance and continue to build towards the next stage of the tournament."

Australia team: Israel Folau, Adam Ashley-Cooper, Tevita Kuridrani, Matt Giteau, Drew Mitchell, Bernard Foley, Will Genia; Scott Sio, Stephen Moore, Sekope Kepu, Kane Douglas, Dean Mumm, Scott Fardy, Sean McMahon, David Pocock.

Replacements: Tatafu Polota-Nau, James Slipper, Greg Holmes, Rob Simmons, Ben McCalman, Nick Phipps, Matt Toomua, Kurtley Beale.