For the first time in his tenure as Wallabies coach, Michael Cheika has named an unchanged 23 in back-to-back Tests for the first time, after he took over the side in 2014.
Cheika has stuck with his winning side and resisted the urge to tinker, despite the return of Ned hanigan (injury) and Rory Arnold (suspension).
The Wallabies pulled off an inspiring win over the World No.2 in Brisbane last week, with their crushing defence propelling them to the 18-9 win, while they are set to retain their bold kicking strategy as they head into game two.
As expected Ireland rang in the changes with for the must win clash, with superstar fly-half Johnny Sexton returning to the starting line up.
Sexton replaces young five eighth Joey Carbery, re-establishing his successful scrum-base partnership with halfback Conor Murray for the second Test at Melbourne's AAMI Park on Saturday night.
Coach Joe Schmidt has made big changes to his forwards with a new front row of Cian Healy, Niall Scannell and Tadhg Furlong while Dan Leavey comes in at openside flanker ahead of Jordi Murphy and Devin Toner joins James Ryan in the second row.
Leavey will be crucial in the breakdown battle where David Pocock dominated for the Wallabies during the first Test win in Brisbane.
Star outside centre Gary Ringrose comes in, with Robbie Henshaw switching to inside centre and Andrew Conway takes over on the right wing from Jacob Stockdale.
The Wallabies last played Ireland in Melbourne 10 years ago where they scored a hard fought 18-12 win.
Wallabies: Israel Folau; Marika Koroibete, Samu Kerevi, Kurtley Beale, Dane Haylett-Petty; Bernard Foley, Will Genia; Caleb Timu, Michael Hooper, David Pocock; Adam Coleman, Izack Rodda; Sekope Kepu, Brandon Paenga-Amosa, Scott Sio. Reserves: Tolu Latu, Tom Alaalatoa, Taniela Tupou, Rob Simmons, Lukhan Tui, Pete Samu, Nick Phipps, Reece Hodge.
Ireland: Rob Kearney; Andrew Conway, Garry Ringrose, Robbie Henshaw, Keith Earls; Johnny Sexton, Connor Murray; CJ Stander, Dan Leavy, Peter O'Mahony (c); James Ryan, Devin Toner; Tadhg Furlong, Niall Scannell, Cian Healy. Reserves: Rob Herring, Jack McGrath, Andrew Porter, Tadhg Beirne, Jordi Murphy, John Cooney, Joey Carbery, Jordan Larmour.