George North, Dan Lydiate and Jamie Roberts will be availability to face the Wallabies for Wales despite the game falling outside the IRB Test window.
There had been fears that many of Wales' foreign-based stars would be unavailable for the last of their four November internationals against South Africa, Argentina, Tonga and Australia.
However, Racing Metro flank Lydiate has revealed that his contract allows him to be released for one extra international per year and that his club team-mate Roberts has the same situation.
"Yes, I am available," Lydiate told the reporters after his side's draw with the Scarlets in the Heineken Cup.
"It is part of my contract. I am allowed to play one match outside of the window, either the one in the autumn or a match in the summer like the ones against the Barbarians. So I'll choose the autumn one."
Northampton wing North also looks set to be given an extra week by his club thanks to a similar clause in his contract.
Saints Director of Rugby Jim Mallinder said they encouraged rather than prevented their players from featuring in internationals.
"I would not talk about individual players' contracts, but we want all our players to play international rugby and we support them in their quest to do that," said Mallinder.