Ireland have sprung two big selection surprises for this weekend's clash with Australia while also reuniting big guns Brian O'Driscoll and Paul O'Connell for their first start together in the green jersey since the 2011 Rugby World Cup.
New Kiwi-born coach Joe Schmidt dumped British and Irish Lions halfback Conor Murray as well as veteran centre Gordon D'Arcy in two shocks for Sunday morning's (AEDT) Test at Dublin's Aviva Stadium.
Schmidt has swung six changes to the starting team which beat Samoa 40-9, including the return of captain O'Connell after he played off the bench last week.
Abrasive second-rower O'Connell and centre great O'Driscoll have both been hit with injuries since the last World Cup when Ireland upset the Wallabies 15-6 in the group stages.
Eleven Ireland survivors will again start this weekend, while Australia only have four in Will Genia, Quade Cooper, James Horwill and Adam Ashley-Cooper.
As expected, Irish playmaker Jonny Sexton, flanker Sean O'Brien and prop Cian Healy were also returned to the starting side after being rested against Samoa.
The promotion of Eoin Reddan for Murray was the biggest surprise, while D'Arcy was dumped from the squad altogether as youngster Luke Marshall was given his shot in the centres with O'Driscoll.
Murray produced an influential cameo for the Lions in the series-deciding third Test in Sydney as the tourists scored three second-half tries for a 41-16 thumping of Australia.
But Reddan's slick ball distribution and greater experience alongside five-eighth Sexton in a Leinster-dominated outfit has been preferred.
Schmidt denied the changes were due to poor form and argued he was trying to build depth after taking over from Declan Kidney following a poor Six Nations campaign.
"This is what our aim is, which is to build a squad of around 35 players all capable of playing in the starting 15," he said.
"It had become a little narrow in terms of selection in the past few years."
The Wallabies made two personnel changes to the starting pack which beat Italy 50-20 in Turin last week with Scott Fardy returning to the back-row and Sekope Kepu replacing Ben Alexander at tight-head.
"We will need to be on our guard as Australia are on an upward curve in which consistency in selection of late has helped," Schmidt said.
"They scored 50 points last weekend against Italy and did the same to the Argentinians in (Rosario) and there are not many sides who have managed to do that to the Pumas in their own backyard in recent times."
Ireland: Rob Kearney, Tommy Bowe, Brian O'Driscoll, Luke Marshall, Fergus McFadden, Jonny Sexton, Eoin Reddan; Jamie Heaslip, Sean O'Brien, Peter O'Mahony, Paul O'Connell, Devin Toner, Mike Ross, Rory Best, Cian Healy. Res: Sean Cronin, Jack McGrath, Stephen Archer, Mike McCarthy, Kevin McLaughlin, Conor Murray, Ian Madigan, Robbie Henshaw.
