Melbourne - Six Nations champions Ireland turned to key men Johnny Sexton and Cian Healy on Thursday as they look to salvage their series in the do-or-die second Test against Australia in Melbourne. 

The veterans watched on from the reserves bench last weekend as Australia won 18-9 in Brisbane to end the world number two team's unbeaten stretch of 12 internationals. 

Coach Joe Schmidt played understudy Joey Carbery at number 10 with an eye to his options for next year's World Cup in Japan, but has turned to 32-year-old Leinster ace Sexton to guide the Irish attack on Saturday. 

Sexton will be making his 75th appearance for his country, while loose-head prop Healy lines up for his 80th cap as one of eight team changes for the second of three Tests. 

"It's not something I've done with Ireland for a long, long time so it needed a bit of getting used to," Sexton said of his rare role as a reserve. 

"It's a different type of game when you're on the bench. You have a lot of nervous energy. It's all about starting for everybody really, that's why you want to get the starting place." 

The Wallabies, under former Leinster boss Michael Cheika, were physical in Brisbane and they will be unchanged in Melbourne for the first time in the coach's four-year tenure. 

"We expected it (last week)," Sexton said. "Under Michael Cheika, they will bring that and we spoke about that; we know him better than anyone, really. 

"We knew it was coming, but we probably didn't deal with it as well as we could have in terms of allowing them to come out of the line and hit us like they did. 

"We'll learn from it and I'm sure they'll bring the same intensity this week. Michael is a pretty relentless character and he will demand the same of them this week." 

Sexton, who is expected to probe for weaknesses in the Wallabies through his trademark kicking, paid tribute to Australia's backline in Brisbane. 

"They've got quality throughout the team. When you look at their backline, it's scary the amount of pace and ball players they have at the same time," he said. 

Schmidt is also looking to neutralise the impact of David Pocock and Michael Hooper over the Irish ball by naming Dan Leavy at openside flank. 

Just three forwards from the first Test defeat have been retained with James Ryan, CJ Stander and captain Peter O'Mahony keeping their places as five Leinster men bolster their pack. 

In contrast, Australia are unchanged with Cheika retaining the same match-day squad in back-to-back Tests for the first time in his 46 games in charge. 

It means there is no place for flanker Ned Hanigan, who is back from injury, or lock Rory Arnold who is returning from a suspension. 

Ireland, who haven't won in 11 internationals in Australia dating back to 1979, need a victory in Melbourne to take the series to a decider in Sydney next week.

Teams:

Australia

15 Israel Folau, 14 Dane Haylett-Petty, 13 Samu Kerevi, 12 Kurtley Beale, 11 Marika Koroibete, 10 Bernard Foley, 9 Will Genia, 8 Caleb Timu, 7 Michael Hooper (captain) 6 David Pocock, 5 Adam Coleman, 4 Izack Rodda, 3 Sekope Kepu, 2 Brandon Paenga-Amosa, 1 Scott Sio 

Substitutes: 16 Tolu Latu, 17 Tom Robertson, 18 Taniela Tupou, 19 Rob Simmons, 20 Lukhan Tui, 21 Pete Samu, 22 Nick Phipps 23 Reece Hodge

Ireland 

15 Rob Kearney, 14 Andrew Conway, 13 Garry Ringrose, 12 Robbie Henshaw, 11 Keith Earls, 10 Johnny Sexton, 9 Conor Murray, 8 CJ Stander, 7 Dan Leavy, 6 Peter O'Mahony (captain), 5 James Ryan, 4 Devin Toner, 3 Tadhg Furlong, 2 Niall Scannell, 1 Cian Healy

Substitutes: 16 Rob Herring, 17 Jack McGrath, 18 Andrew Porter, 19 Tadhg Beirne, 20 Jordi Murphy, 21 John Cooney, 22 Joey Carbery, 23 Jordan Larmour