Wales second row Cory Hill could "possibly" be out of the World Cup without playing a game, says coach Warren Gatland.
Wales had only two fit locks - Alun Wyn Jones and Jake Ball - for the 43-12 win against Georgia in Toyota City with back row Aaron Shingler filling in.
Hill is recovering from a stress fracture in a leg, with Adam Beard recovering from appendicitis surgery.
Asked if Hill was out of the tournament, Gatland said: "Possibly."
He added: "In terms of fitness he will go back to the UK if he is not right. We will assess him tomorrow and just see what progress he has made and how his injury is.
"If it is not good news then he will go back. If they think they can get him to recover then he will stay out. We are just going to assess it overnight."
Wales face Australia in Tokyo on Sunday, 29 September, with Beard already ruled unlikely to be fit.
If Hill has to return home, his place is likely to be taken by Ospreys second row Bradley Davies.
"He would be the natural choice because he's spent that time with us," said Wales forwards coach Robin McBryde.
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