Australia captain Michael Hooper and lock Adam Coleman have been withdrawn from the squad for their final Pool D match against Georgia because of minor injuries, the team said on Thursday.
Hooper and Coleman had been named among the replacements for Friday's match at Shizuoka Stadium so Rob Simmons and Lukhan Salakaia-Loto will now sit on the bench and cover the second and back rows respectively.
"Both of them were deemed to have a few niggles that they didn't want to push on for this one with now a confirmed quarter-final berth against England," team spokesman Chris Ford told reporters.
The cancellation of Saturday's Pool C match between England and France because of Typhoon Hagibis means Australia will play the English in the last eight if, as expected, Wales beat Uruguay in their final Pool D match.
Lock Simmons now looks set to win his 100th cap off the bench on Friday, a notable achievement for a player who made his debut against South Africa in 2010.
"The big man from Theodore," David Pocock said, referring to Simmons's tiny home town in rural Queensland.
"He's a well-loved member of the team. One of those guys who goes about his business, very dependable. He's clearly been pretty robust to play the number of games in the time he has.
"Pretty amazing to have someone like him on the bench ... with that experience, knowing that he steps up when he's needed."
Although Simmons lacks the physicality of some locks, his reliability in organizing the sometimes rocky Australia lineout has often made him an indispensable part of the team for much of the last nine years.
"He's quite knowledgeable around the lineout and that's where I learned a lot about calling the lineout from," said lock Izack Rodda, who also played with Simmons at the Queensland Reds. "It's definitely one of his strengths."
With Hooper on the bench in the initial team, Pocock was always going to captain the side in Australia's first test against Georgia.
"There'll be plenty of feeling in it, I'm sure," the flanker said. "Georgia, we've seen how good they are around set piece. They relish it, their forward pack loves to rumble it forward so that's a big threat for us to deal with and from there try and play."
Australia: 15-Kurtley Beale, 14-Jordan Petaia, 13-James O’Connor, 12-Samu Kerevi, 11-Marika Koroibete, 10-Matt To'omua, 9-Nic White, 8-Isi Naisarani, 7-David Pocock (captain), 6-Jack Dempsey, 5-Rory Arnold, 4-Izack Rodda, 3-Sekope Kepu, 2-Tolu Latu, 1-Scott Sio
Replacements: 16-Jordan Uelese, 17-James Slipper, 18-Taniela Tupou, 19-Lukhan Salakaia-Loto, 20-Rob Simmons, 21-Will Genia, 22-Christian Lealiifano, 23-Dane Haylett-Petty.© (c) Copyright Thomson Reuters 2019.