Jordan Petaia has taken every opportunity in his stride this year and true to form the teenager handled this week’s injury heartbreak “like a pro”, skipper Michael Hooper says.

Petaia was named to make his debut on Thursday local time but a hamstring injury suffered in training later that day forced him out of the match.

Though it was just a small twinge, it was considered too much of a risk to put the teenager in a Test debut anywhere short of 100 per cent.

Hooper said while it would be devastating for the youngster to miss out on a chance to debut but Petaia wasn't letting the setback get to him.

“(He handled it) like a pro,” he said.

“You can’t do anything, he’s been very well-supported by the team.

“To get ruled out that late for your debut it would be shattering but the guys have been really tight sticking around him and he will be back up for many more I’m sure of it."

Petaia will be replaced by winger Marika Koroibete in the starting XV with coaches opting for a specialist winger rather than fellow young gun Tom Banks, whose preferred spot is fullback.

Lock Rory Arnold also pulled out of the Test after fracturing his eye socket in a training collision this week, effectively ending his season with two matches left.

Though he is expected to be fine to travel to London on Sunday local time, Arnold will be up against it to play against England.

"Rory is one of those ones that shouldn’t happen," Hooper said.

"Really unlucky again and he is like Jordan, we’ve obviously seen a bit more of Rory, he’s been on of the guys toiling behind the scenes.

"Getting another opportunity here on the weekend.

"Tough that his season is essentially over there from a session on Thursday but the way these things go, that’s the sport we play."

It’s far from the first time the Wallabies have had to rejig their team on the eve of a Test with Taniela Tupou, David Pocock, Israel Folau, Adam Coleman, Hooper and Tatafu Polota-Nau all forced out of lineups late in Test weeks this season.

Hooper said that roll of injuries meant they were ready to handle unexpected hurdles late in the piece.

"We’re up against some challenges throughout the year and it’s certainly building some resilience because these things can happen and that is part of the game we play," he said.

"It’s not a new thing at the back end of the season.

"We’re building depth which is one positive and the ability for this happen and someone to step in and have confidence in what they can deliver off not the usual preparation has been a good thing."

Australia is looking for an 18th win over Italy, a team they have never lost to, this weekend when they play off in Padova and Hooper said the key to that would be staying calm.

"Our defence has been improving so looking for that to continue to go up," he said.

"The Italians have a really good way of playing. A nice structured way, they’ve got a good forward pack, some good carriers, particularly through their back row. Really solid.

"So for our guys it’s firstly nullifying their stuff and what the Italians are going to bring to the game, just feeling relaxed, feeling like they can bring their skillset to the parts of the field in attack.

"That’s what I would love to see from the team. We have been doing that in bits but not consistently.

"Last week we sat here and talked about consistency. It’s that - it’s momentum, it’s guys building that confidence. This part of the season is really important and guys backing their skill."

The Wallabies take on Italy on Saturday November 17, kicking off at 3pm local, 1am AEDT, LIVE on beIN Sports Channel 515 and SBS.

TEAM

IN: Folau Fainga’a, Jake Gordon Marika Koroibete, Adam Ashley-Cooper, Jermaine Ainsley, Pete Samu

OUT: Tolu Latu, Sefa Naivalu, Ned Hanigan, Nick Phipps, Jack Maddocks, Allan Alaalatoa

Wallabies to face Italy

1. Scott Sio (53 Tests)

2. Folau Fainga’a (6 Tests)

3. Taniela Tupou (10 Tests)

4. Izack Rodda (15 Tests)

5. Adam Coleman (29 Tests)

6. Jack Dempsey (8 Tests)

7. Michael Hooper (c) (89 Tests)

8. David Pocock (76 Tests)

9. Jake Gordon*

10. Matt To’omua (40 Tests)

11. Marika Koroibete (18 Tests)

12. Bernard Foley (66 Tests)

13. Samu Kerevi (23 Tests)

14. Adam Ashley-Cooper (116 Tests)

15. Israel Folau (71 Tests)

Reserves

16. Tatafu Polota-Nau (87 Tests)

17. Jermaine Ainsley (1 Test)

18. Sekope Kepu (101 Tests)

19. Rob Simmons (92 Tests)

20. Pete Samu (7 Tests)

21. Will Genia (98 Tests)

22. Kurtley Beale (82 Tests)

23. Dane Haylett-Petty (29 Tests)

*denotes uncapped