Ireland centre Robbie Henshaw has been ruled out of Saturday's autumn international against South Africa and will be replaced by Stuart McCloskey.
Leinster player Henshaw was absent from training on Friday morning due to a hamstring issue.
Ulster’s McCloskey will step up from the bench to partner Garry Ringrose in midfield and win his seventh Test cap.
Ireland forwards coach Paul O'Connell praised the 30-year-old's patience and believes he is ready to make his mark for Andy Farrell's men.
"I'm very confident about Stuart," said O'Connell. "Andy is obviously disappointed and we're all disappointed to miss out on Robbie. He's a world-class player, playing very well.
"But Stuart has had some tough days where he has been up here training and a coach has had to have a conversation with him before the team is announced and that has happened an awful lot.
"He's always stuck with it and seems to be getting better and better and better as a player and never disheartened.
"For Stuart to come in and play it just broadens the group again for us and we're really confident in his ability and his smarts, the experience he has in that position, it's a great replacement."
McCloskey won his last Ireland caps in July 2021, scoring a try in each of the wins over Japan and the USA. He was called into the Ireland squad during last summer's tour of New Zealand after Ulster team-mate James Hume was ruled out through injury and started in the win over the Maori All Blacks.
Head coach Andy Farrell has added Jimmy O'Brien to his replacements for the visit of the Springboks.
O'Brien also featured in that 30-24 victory in Wellington and will win his first Ireland cap if introduced against South Africa.
📋 Team Update.— Irish Rugby (@IrishRugby) November 4, 2022
Robbie Henshaw has been unfortunately ruled out of tomorrow's game through injury.
Stuart McCloskey comes into the starting team, with Jimmy O’Brien named on the bench.#TeamOfUs | #IREvSA pic.twitter.com/jBGly6iAeo
Ireland have not locked horns with the Springboks since a 38-3 home win in 2017 but will not have to wait so long for the next meeting as the countries have been drawn together in the pool stage of the 2023 Rugby World Cup.
"The lessons learned are going to be vast for both sides, win or lose," said Ireland head coach Andy Farrell.
"I suppose the team that loses will learn a little bit more and know which direction they want to go, not just game plan-wise but player-wise. That's why I think this is priceless for both teams as a match-up.
"It’s exciting for what’s down the line but in the here and now it is good as well."
Ireland: Hugo Keenan; Robert Baloucoune, Garry Ringrose, Stuart McCloskey, Mack Hansen; Johnny Sexton (capt), Conor Murray; Andrew Porter, Dan Sheehan, Tadhg Furlong; Tadhg Beirne, James Ryan; Peter O'Mahony, Josh van der Flier, Caelan Doris
Replacements: Rob Herring, Cian Healy, Finlay Bealham, Kieran Treadwell, Jack Conan, Jamison Gibson Park, Joey Carbery, Jimmy O'Brien
Additional reporting: PA
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