Toyota City - Wales centre Hadleigh Parkes fractured a bone in his hand in the World Cup opener against Georgia, but should be fit for Sunday's Pool D showdown against Australia.

Coach Warren Gatland confirmed the Kiwi-born midfielder had suffered "a bit of a bone fracture."

Gatland will be hoping Parkes can take the field against the Wallabies given his key role in midfield, where he has forged a potent partnership in both defence and attack with Jonathan Davies.

"They think he'll be okay to pad that up and it shouldn't be an issue for next week," Gatland said of Parkes.

"Guys are a bit battered and sore as you'd expect after playing a tough, physical team like Georgia."

There was disappointment however, for highly-regarded lock Cory Hill, who co-captained Wales to a series win in Argentina last year but will miss the rest of the World Cup after failing to make sufficient progress from a stress fracture of his leg.

Hill, who has not played since Wales' win over England in February en route to last season's Grand Slam, underwent further tests on Tuesday.

"Cory Hill has been released... after being unable to recover significantly from a stress fracture of his fibula," the Welsh Rugby Union said in a statement.

"Bradley Davies, capped 65 times by Wales and who has featured in two previous Rugby World Cups, has been named as his injury replacement and will arrive in Japan on Wednesday."

Davies offers a very physical game, a powerful ball runner who is a competent line-out operator and also a very popular character in the squad.

Wales raced out to a 29-0 half-time lead against Georgia in Toyota City on Monday, before the two sides traded two converted tries in the second-half to leave the final score 43-14.

Jonathan Davies' opening try came from a set piece move from a scrum and winger Josh Adams followed that up with a beauty of a try from a well-rehearsed line-out move that caught a leaden-footed Georgian defence napping.

"It was a nice set-piece move and I managed to finish it off. I was happy with that," said Adams.

"We'd been itching for a game for so long.

"The energy and the keenness showed in the first-half where we were fluent. We were ruthless and everything we did went to plan. We will need to do that again on Sunday (against Australia)."