LONDON - World rankings have become the elephant in the room for the Wallabies, who risk dropping out of the coveted top four this weekend if they lose to England at Twickenham.
Injured Wallabies inside centre Pat McCabe said the players understood the extra significance their three remaining European tour Tests had taken on with the draw for the 2015 Rugby World Cup on December 3 fast approaching.
In a first for the draw, the top four seeded teams will avoid each other until the knockout stages of the World Cup to be held in England.
"While we don't speak about those things, everyone's aware of them and as much as we might not read everything in the press, we are completely aware of how big this game is in so many ways, especially from a World Cup perspective," McCabe told AAP.
"And it's not just us, they have plenty to play for too on that front."
Australia placed themselves in a vulnerable position with their 33-6 loss to France in Paris last weekend.
The defeat resulted in Robbie Deans' side dropping from second to third in the world rankings with South Africa jumping from third to second with a win over Scotland.
France leapfrogged England into fifth place, meaning the host nation will be desperate to beat the Wallabies and secure a top four berth.
The numbers have been crunched ahead of this weekend's fixtures and there are various scenarios that would see the Wallabies drop out of the top group.
The most basic of them is if Australia lose to England on Saturday (Sunday Fiji time), France beats Argentina and South Africa doesn't lose to Scotland by more than 15 points, then the Wallabies would drop out of the top four.
The IRB rankings are calculated using a points exchange system in which sides take points off each other based on the match result.
The exchanges are based on the match result, the relative strength of each team and the margin of victory, and there is an allowance for home advantage.
Australia have plenty of incentive to win the match, for not only would they prevent England from winning a third straight Cook Cup, but they could also jump as high as second in the world rankings.