Petaia only made his debut for the Wallabies at this World Cup, becoming their youngest ever player in the competition. Now he's playing in the country's biggest match in four years. "The way his demeanor is," Cheika said of the 19-year-old Petaia, "you wouldn't think he was picked. He was just loping around as per normal so it's going to be great. I trust him infinitely and that's why he's been chosen."
Petaia, one of the most highly rated youngsters in Australian rugby, was called up for the first time last year ahead of a Bledisloe Cup game against New Zealand but didn't make the match-day squad. He has barely played a top-level game in 2019 because of a foot injury sustained in the second round of the Super Rugby season in March for Queensland Reds. A hamstring injury meant he didn't play for Australia's first two pool games at the World Cup, against Fiji and Wales, but did enough in appearances of the left and right wing against Uruguay and Georgia, respectively, to convince Cheika he is ready for England.
"I wouldn't be looking at the age of players at either end of the spectrum," Cheika said. "Yes, it's going to be fast and aggressive and all that type of stuff and I know that lad will rise up to that challenge. I know it. I've seen it in him, so I know he will on Saturday."
Cheika is staking his job on this World Cup, having previously said he'll leave the post if Australia doesn't become champion for a record-tying third time. So this could be his last match, with England starting as favorite having won all of the teams' six meetings in this World Cup cycle.
Petaia will join vice-captain Samu Kerevi in a new center combination, relegating James O'Connor to the bench, but that wasn't the only interesting selection. Will Genia and Christian Leali'ifano were named as Australia's halfbacks, having last started a test together in July, so Nic White and Matt Toomua were among the back reserves bench that does not feature utility Dane Haylett-Petty.
Reece Hodge, meanwhile, is straight back on the wing after serving a three-game suspension for his illegal tackle against Fiji in the opening pool game. "He's got a certain skill-set that we like, and he's got a great work ethic as well," Cheika said of Hodge. "It was a tough decision because there's a guy like Dane Haylett-Petty who's not even in the team but I just think he'll be a really good fit for this game."
Michael Hooper will return to lead the Wallabies in his 99th test as Cheika persists with his backrow strategy of playing David Pocock, a regular openside, at No. 6. Australia and England have met six times at the Rugby World Cup, with each team winning three times. The Australians won the most-recent of those in 2015, a victory that contributed to England's group-stage exit at the tournament it was hosting.
But England has responded to that loss by winning the last six head-to-head meetings, all under the guidance of ex-Australia coach Eddie Jones. The winner at Oita on Saturday will meet either defending champion New Zealand or Ireland in the semifinals.
Australia: Kurtley Beale, Reece Hodge, Jordan Petaia, Samu Kerevi, Marika Koroibete, Christian Leali'ifano, Will Genia; Isi Naisarani, Michael Hooper (captain), David Pocock, Rory Arnold, Izack Rodda, Allan Alaalatoa, Tolu Latu, Scott Sio. Reserves: Jordan Uelese, James Slipper, Taniela Tupou, Adam Coleman, Lukhan Salakaia-Loto, Nic White, Matt Toomua, James O'Connor.
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