Warren Gatland has admitted Wales lock Cory Hill may not be able to play any part in the World Cup.
Gatland said that the Dragons forward will be assessed on Tuesday. A decision then looks likely to be made on Hill, who has been battling to overcome a stress fracture of his leg and has not played since February.
Asked at Wales' post-match press conference following a 43-14 World Cup victory over Georgia if Hill was out of the tournament, Gatland said: "Possibly.
"If he doesn't return to fitness, he will go back to the UK. We're going to assess him tomorrow and see what sort of progress he has made.
"If it's not good news, he will go back. If they think he can recover, then he will stay out. We are going to assess that overnight."
Centre Hadleigh Parkes suffered "a bit of a bone fracture" in his hand against Georgia, but he is not expected to be a fitness issue for next Sunday's crucial Pool D showdown against Australia.
Gatland said: "We have been watching the games the last few days, and the guys were itching to get on the field.
"I'm pleased with our first-half performance - we were pretty clinical - but we let things slip in the second half. We lost some continuity by making some changes and keeping players as fresh as we can."
Wales beat Australia on their last meeting 10 months ago, which ended a long run of defeats against the Wallabies, and Gatland added: "I think we can take a lot of confidence from that. They are a tough side.
"We've had some really tight games with them over the years. We've got to go into that game with a lot of confidence."