I'd pick this team:
1. Gethin Jenkins, 2. Scott Baldwin, 3. Samson Lee, 4. Luke Charteris, 5. Alun Wyn Jones, 6. Sam Warburton, 7. Justin Tipuric, 8. Taulupe Faletau, 9. Gareth Davies, 10. Dan Biggar, 11. Liam Williams, 12. Jamie Roberts, 13. Tyler Morgan, 14. George North, 15. Gareth Anscombe
BENCH: 16. Ken Owens, 17. Paul James, 18. Tomas Francis, 19. Jake Ball, 20. Ross Moriarty, 21. Lloyd Williams, 22. Rhys Priestland, 23. Matthew Morgan
Retain Gethin, because I don't don't think James will add a huge amount to the scrum in comparison. Plus we need to go hard at the breakdown, hence the reason for the Warburic combination. Moriarty is on the bench as I feel he would offer more impact than Lydiate with his carrying later in the game. Lydiate to come back in for the quarter final. Only for this game bare in mind, to counter the threat of Pocock (I know Hooper is gone, but Poey makes most of their turnovers). In the backs Williams moves to wing, to accomodate Anscombe at the back. Cuthbert simply should not be there anymore and with Williams to 11, Anscombe is the best option for this game, as he has a good kicking game and is decent with ball in hand. Matthew Morgan is great but I'm scared he'll run us into trouble at some stage, so bring him on for spark later in the match.
I do feel they will go with Lydiate again though, Gatland is pretty consistent in that regard. I think with Hooper out it might change his mind.
For the Aussies, I wonder if they'll shift Pocock to 7 and put McCalman at 8 or if they'll put McMahon to 7 and continue the dual openside combination. Will be interesting to see.
I do think the Wallabies will get up, but I don't its going to be a blowout. In the 7 times we've lost since that 3rd place play-off last world cup, the largest margin of victory has been 8, with the rest of the matches within 7 points. There has been 2 last minute victories and 2 won in the last 5 minutes. So it will be tight. They are a better team now though than before so I reckon they will take it by 10. This is a tournament defining game for Wales in my opinion. If we win, I can see a road to the final for us with all the teams in that half of the draw being teams we know how to win against. In fact, if we win, I wonder what the possibility of a rematch between the teams in the final would be? It's happened last 2 world cups so it could happen again but only if Wales win. If we go into the other side of the draw, it's game over unfortunately. Anyway bring it on, can't wait!