Scarlets wing Mark Jones replaces Cardiff Blues’ teenage sensation Leigh Halfpenny, with lock Ian Gough taking over from his injured Ospreys colleague Ian Evans.

Evans will not play again this season after suffering knee ligament damage during the 29-9 loss to New Zealand three days ago and he faces surgery during the next couple of weeks.

And Jones, who has won 42 caps, gains only his second start of the autumn after a knee injury sidelined him for Wales’ narrow defeat against world champions South Africa 17 days ago.

One switch on the bench sees Scarlets scrum-half Martin Roberts in for Dwayne Peel.

Because the Wallabies clash falls outside the International Rugby Board autumn Test window, Peel’s club commitments take priority, and Sale Sharks are in Guinness Premiership action against Leicester on Friday night.

The Sharks have decided to make Peel unavailable for Wales.

Talks, meanwhile, between Welsh Rugby Union chief executive Roger Lewis, Rugby Football Union chairman Martyn Thomas and Gloucester chairman Tom Walkinshaw secured Gareth Cooper’s release from Kingsholm to face Australia.

Gatland said: “In Mark Jones, we have a player who has been in form, but was kept out after being injured for our opening fixture by Leigh’s impressive showing.

“But he now has an opportunity to re-stake his claim, and we are sure he will rise to that particular challenge.

“Leigh has represented himself well in his first three caps for his country and made a real impact on the international scene.

“But he is a young man, and after three huge games in succession, we have decided to look after him and have him to sit this one out.

“Ian Gough brings a wealth of experience to the second-row, and although Luke Charteris can be pleased with his performance when he went on against the All Blacks last weekend, we have preferred him as an option on the bench who can come on and make an impact.”

Victory for Wales over Australia could see them climb from their present IRB world ranking of sixth.

A win by 15 points or more could even lift them into the top four ahead of next Monday’s 2011 World Cup draw in London.

Wales team: L Byrne (Ospreys); M Jones (Scarlets), T Shanklin (Cardiff Blues), J Roberts (Cardiff Blues), S Williams (Ospreys); S Jones (Scarlets), G Cooper (Gloucester); G Jenkins (Cardiff Blues), M Rees (Scarlets), A Jones (Ospreys), I Gough (Ospreys), A-W Jones (Ospreys), R Jones (Ospreys, capt), M Williams (Cardiff Blues), A Powell (Cardiff Blues).

Replacements: R Hibbard (Ospreys), J Yapp (Cardiff Blues), L Charteris (Newport Gwent Dragons), D Jones (Scarlets), M Roberts (Scarlets), J Hook (Ospreys), A Bishop (Ospreys).