The Wallabies will field entirely different starting XVs in their opening two pool games as a way to deal with the challenge of three tests in 11 days.
Assistant coach Stephen Larkham said the Wallabies squad would be split down the middle, meaning one starting side - ostensibly the strongest - will be chosen to play Fiji on September 24 (NZT) and a second, and different, XV will run on against Uruguay on September 28.
Some will cross over on the benches but no starting players from the Wallabies' A side will back up and start against Uruguay as well. They'll instead begin to turn towards the big clash against England on October 4.
"Once we get over there [to England], it is 10 days before the first game and we are splitting into two teams basically," Larkham told Sydney's Daily Telegraph.
In past World Cups, Wallabies' teams to play against minnow nations have included many "reserves" but always retained a core of top-team starters. Quade Cooper played in every test at the 2011 Rugby World Cup. But changes to the World Cup fixture list after the 2011 tournament, mean Michael Cheika's Wallabies had to plan for a four-day turnaround for the first time since 1999.