Shaun Marsh has replaced his younger brother Mitchell in Australia's fourth Test XI for the crucial match at Trent Bridge, with England to bowl first after winning the toss.
Australia captain Michael Clarke confirmed the change at the coin toss, where he called incorrectly giving first choice to Alastair Cook who opted to unleash his seam attack minus James Anderson on a green deck.
The speculation of Australia's decision to dispense with the allrounder and opt for an extra batsman had swept through Trent Bridge early on Thursday, and was strengthened with Mitch Marsh not warming up with the bulk of Australia's squad, instead tossing a football around with recent squad addition Pat Cummins.
Shaun had been hotly tipped to come in after scoring two centuries in Australia's warm-up matches, with Western Australian batsman Adam Voges expected to be the unlucky man to miss out after a below par series so far.
Voges, who scored a century on debut agains the West Indies, has 73 runs at 14.6 this series with a top score of 31.
The addition of Shaun Marsh, who opened the batting in two Tests in the West Indies while Chris Rogers was out with concussion symptoms, also left a question mark over the batting order.
Australia have long preached that selectors pick the team, the captain sets the batting order, so it was with some interest that Clarke moved himself back to No.5, a spot where he has enjoyed the most success in his long and illustrious career.
However, Clarke has been struggling in this current series with 94 runs at 18.8 in the three Tests so far.
"Shaun's always batted in front of me in the Test team," said Clarke, after losing the toss.
"He's opened the batting for Australia and batted at number three – he's a top-order player."
Mitch Marsh had come into the Australian side for the second Test at Lord's replacing fellow allrounder Shane Watson. However, he has scored just 45 runs after playing two Tests, four less than Watson scored in Australia's defeat at Cardiff.
Marsh picked up three wickets in 19 valuable overs for the Australians.
The move to dispense with an allrounder will limit Australia's bowling options and was something Clarke touched on in his Test-eve press conference on Wednesday.
"I'd like everyone in the team to be able to bowl," Clarke said ahead of the Trent Bridge encounter.
"I think it's good as a captain if everyone could bat and everyone could bowl. But I don't know what XI the selectors are going to go for, I think there's strengths to having the more people who can bowl the better, no doubt about that.
"I don't think it's necessarily Adam Voges (who will go out), I think he's been close."
The position swap by the sons of former Australian opener Geoff Marsh echoes a similar move made by selectors in the early 1990s when Mark Waugh was called up for his Test debut at the expense of his twin brother, Steve.
Mark Waugh, called in for the fourth Test of the 1990-91 Ashes series at the Adelaide Oval, famously scored a century on debut. Steve was later recalled for two Tests against the West Indies in 1991 but spent 18 months on the outer until a recall for the West Indies tour of Australia in 1992-93, cementing his spot with a century in the third Test.
Australia: David Warner, Chris Rogers, Steve Smith, Shaun Marsh, Michael Clarke (c), Adam Voges, Peter Nevill (wk), Mitchell Johnson, Mitchell Starc, Josh Hazlewood, Nathan Lyon.
England: Adam Lyth, Alastair Cook (c), Ian Bell, Joe Root, Jonny Bairstow, Ben Stokes, Jos Buttler (wk), Moeen Ali, Stuart Broad, Mark Wood, Steven Finn.
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