Tokyo - Wales are confident their crucial but injury-prone centre pairing of Jonathan Davies and Hadleigh Parkes will be fit for Sunday's Rugby World Cup semi-final against South Africa.

Kick-off is at 11:00 SA time.

Davies was a late withdrawal from the 20-19 quarter-final victory over France last weekend with a knee injury, while Kiwi-born Parkes played with a shoulder contusion and a bone fracture in his hand.

But Wales' skills coach Neil Jenkins said on Wednesday he had "no doubt" the midfield partners would be fit to take on the Springboks in Yokohama.

"As the week progresses, they'll train with us as normal and obviously I'd like to think they'll take a full part in training this week and make themselves available for selection on Sunday," he added.

"These games don't come around very often," added Jenkins, whose 1 090 points in 87 Tests for Wales and four for the British and Irish Lions leave him third in the all-time highest scorers' list behind ex-All Black Dan Carter and England's Jonny Wilkinson.

"I think sometimes if your leg's hanging off, you strap it to yourself to get yourself right and I'm sure they'll do that this week!"

In a sign Wales felt they needed cover in the back-line, they called up Cardiff Blues winger Owen Lane to replace Josh Navidi when the No 8 was ruled out of the rest of the tournament with a hamstring injury.

And Jenkins insisted the winger could play at centre despite spending most of his club career out wide.

"He's a talented rugby player and can play in both positions," Jenkins said. "He's a winger first and foremost, but can play centre for us as well."

Jenkins acknowledged that Davies, as the backs' defensive leader, was particularly important in what promises to be a no-holds barred last-four clash against a physically uncompromising Springbok side.

"He's a key player for us. He's a big player and someone we need fit realistically," he said, Owen Watkin having plugged the gap in the nail-biting victory over the 14-men French.

He said Davies had trained most of last week but didn't feel quite right on the day.

"But it is an important game on Sunday and we need all hands on deck to get through that match," said the coach.

Jenkins said Wales' history should help them prepare for such a massive match. Wales reached the semi-finals in 2011 but lost in the quarter-finals in 2015 to the Springboks.

"We've been there, done it, know what it's like. We've won some big games, lost some big games."

The former flyhalf/fullback added that he hoped the match would not boil down to extra-time, sudden death or a kicking shoot-out should scores be tied.

Semi-finals are bound to be tight, he said, adding the team would have everything prepared in the event of extra time or sudden death.

"From our perspective it would be nice to get it done after the 80 minutes, but I'm sure South Africa feel the same," he said.