Wales duo Liam Williams and Dan Biggar ruled out of clash against Boks

Both players had been selected to start the match in Cardiff, but have been withdrawn as a precautionary measure.

The Welsh Rugby Union said that full-back Williams had a tight hamstring, with Biggar suffering from back irritation.

Cai Evans is promoted from the replacements' bench to make his Test debut as Williams' replacement, while Sam Costelow replaces fly-half Biggar.

Evans' spot on the bench is filled by Scarlets back Tom Rogers.

"Both of them, if we pushed them hard, could play on Saturday, but the decision was made there is no point taking a risk at this stage," said Wales coach Warren Gatland.

"If this was a World Cup semi-final, Dan Biggar would have been fine for the weekend."

Saturday's clash in Cardiff is a last chance for players to impress Gatland, who will announce his 33-strong World Cup squad within 48 hours of the final whistle.

"There is an opportunity for players on Saturday. We will come back as a coaching group after the game and finalise the squad," Gatland said.

"We are confident that those players carrying injuries are going to be available for the first game against Fiji.

"We will get a pretty detailed injury update in terms of all the players in the squad, the ones carrying knocks and when they can return to full-time training and when they are available.

"Potentially, there may be one or two decisions, which has happened in the past, where we are still undecided and we might sleep on it and make a final decision potentially on the Sunday.

"Then it's a matter of notifying the players and announcing the squad on Monday."

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