Halfpenny was due to win his 98th cap and make a first Wales start for 19 months, but assistant coach Jonathan Humphreys said he had suffered a back spasm and would miss the game.

Experienced Cardiff back Liam Williams will replace Halfpenny in the number 15 shirt.

Williams missed Wales' entire Autumn Nations Series campaign this season because of injury, and has not started for his country since last summer's South Africa tour.

Humphreys said: "Unfortunately, Leigh had a back spasm this morning and Liam will be playing.

"I think it's more disappointing for him as a person. He is an unbelievable professional and an unbelievable person.

"He has got to pick himself up again. You feel for him that he's got to pull out at this late stage.

"Liam is good to go."

Meanwhile, Ireland prop Tadhg Furlong has also been ruled out of Saturday's match due to a calf injury.

Connacht's Finlay Bealham will start in place of Furlong at tighthead in Cardiff, with Tom O'Toole providing cover from the bench.

Leinster man Furlong has been sidelined by ankle and calf issues in recent weeks but is progressing well and expected back fit within the next seven days.

Andy Farrell's maiden selection of the tournament contains no further surprises as his side seek to build on a stellar 2022 which propelled them to the top of the world rankings.

HAMISH MCLENNAN

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