There are four changes to the starting XV from last weekend’s match against Fiji.
James Botham and Jac Morgan come into the back row alongside Aaron Wainwright.
Ellis Bevan starts at scrum half and Tom Rogers is named on the wing.
There are three changes among the Wales replacements: Tommy Reffell provides the back row cover, while Rhodri Williams and Eddie James join Sam Costelow as the replacement backs.
Gatland said: “We have had honest reviews after last week’s match.
“There were some things we did well that we are looking to build on, but we need to be more accurate and disciplined especially in key moments.
“We’re expecting an Australia side on a high after their win against England. They are a much-improved side since the summer and have played a number of Test matches since we last met. We know we need to put in an 80-minute performance on Sunday.”
Wales team to face Australia
15. Cameron Winnett (Cardiff Rugby – 8 caps)
14. Tom Rogers (Scarlets – 4 caps)
13. Max Llewellyn (Gloucester Rugby – 3 caps)
12. Ben Thomas (Cardiff Rugby – 5 caps)
11. Blair Murray (Scarlets – 1 cap)
10. Gareth Anscombe (Gloucester Rugby – 38 caps)
9. Ellis Bevan (Cardiff Rugby – 4 caps)
1. Gareth Thomas (Ospreys – 34 caps)
2. Dewi Lake (Ospreys – 16 caps) captain
3. Archie Griffin (Bath Rugby – 4 caps)
4. Will Rowlands (Racing 92 – 34 caps)
5. Adam Beard (Ospreys – 57 caps)
6. James Botham (Cardiff Rugby – 14 caps)
7. Jac Morgan (Ospreys – 16 caps)
8. Aaron Wainwright (Dragons – 51 caps)
Replacements
16. Ryan Elias (Scarlets – 42 caps)
17. Nicky Smith (Leicester Tigers – 47 caps)
18. Keiron Assiratti (Cardiff Rugby – 8 caps)
19. Christ Tshiunza (Exeter Chiefs – 13 caps)
20. Tommy Reffell (Leicester Tigers – 21 caps)
21. Rhodri Williams (Dragons – 3 caps)
22. Sam Costelow (Scarlets – 16 caps)
23. Eddie James (Scarlets – 1 cap)
