Conor Murray will become the eighth Irish player to reach the 100 caps landmark when he starts against world champions South Africa in Saturday's autumn international test match at Lansdowne Road.
The 33-year-old scrum-half gets the opportunity as Jamison Gibson-Park, the man who has replaced him as first choice, has yet to play this term due to a hamstring problem.
It is Murray's first start since the victory over Argentina last November and only his second since the 2021 Six Nations match with England.
His selection reunites him at half-back with his long-time test partner Johnny Sexton, the Ireland captain.
Murray, whose try-scoring form dipped to the extent that he scored just one try in his last 29 tests, is the sixth scrum-half to reach 100 caps.
He joins Australian duo George Gregan and Will Genia, England's Ben Youngs, All Black Aaron Smith and Italy's Alessandro Troncon.
Auckland-born Gibson-Park, who was instrumental in Ireland's historic test series win over his fellow New Zealanders in July, is on the bench.
Head coach Andy Farrell, though, has opted to select Hugo Keenan at full-back even though he too has yet to play this term owing to knee and abdominal injuries.
The 26-year-old has become one of Farrell's key players since he took over after the 2019 World Cup. He has started 17 of the last 18 tests, rested only for last season's Six Nations match with Italy.
The only other significant change in the starting line-up is the selection of Ulster wing Robert Balacoune, who gets the nod as James Lowe is injured.
Ireland are hosting the Springboks for the first time since 2017 when they thrashed the visitors 38-3.
However, two years later, with Rassie Erasmus having replaced Allister Coetzee as head coach and with many of the same players from that defeat, the Boks lifted the World Cup for the third time in their history.
Team (15-1): Hugo Keenan; Robert Baloucoune, Garry Ringrose, Robbie Henshaw, Mack Hansen; Johnny Sexton (capt), Conor Murray; Caelan Doris; Josh van der Flier, Peter O'Mahony; James Ryan, Tadhg Beirne; Tadhg Furlong, Dan Sheehan, Andrew Porter
Replacements: Rob Herring, Cian Healy, Finlay Bealham, Kieran Treadwell, Jack Conan, Jamison Gibson-Park, Joey Carbery, Stuart McCloskey.
Coach: Andy Farrell (ENG)