Ireland will be without both Jamison Gibson-Park and Jack Conan for the upcoming series against South Africa and will feature three uncapped players in their 35-man squad.
The Irish Rugby Football Union confirmed scrum-half Gibson-Park will miss the match with a hamstring injury, while number eight Conan is unavailable for personal reasons.
The latter's absence coincides with a call-up for young Ulster flanker Cormac Izuchukwu, with Jamie Osborne and Sam Prendergast also yet to be capped.
2-game series
The touring team will assemble at the IRFU High Performance Centre in Dublin on Thursday to begin preparations for the two-match Test series against the Springboks.
Andy Farrell's side will travel to Johannesburg on Tuesday 25 June for a highly anticipated series against the defending Rugby World Cup champions.
The head coach opted to nominate Prendergast in preference to fellow Leinster fly-halves Ross and Harry Byrne, with Jack Crowley and Ciaran Frawley also in the running for the no.10 spot.
Caolin Braid, Craig Casey and Conor Murray will play at scrum-half, with Robbie Henshaw, Bundee Aki, Stuart McCloskey, Garry Ringrose and Osborne at centre.
The full-backs consist of Jordan Larmour, James Rowe, Jimmy O'Brien and Jacob Stockdale, with the versatile Frawley able to cover the full-back jersey if required.
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Finlay Bealham, Tadhg Furlong, Cian Healy, Oli Yeager, Tom O'Toole and Andrew Porter will play as props, with Rob Herring, Ronan Kelleher and Dan Sheehan at hooker.
Farrell's second-row selection will be Tadhg Byrne, Joe McCarthy and James Ryan, with Ryan Baird, Keiran Doris, Kian Prendergast, Josh van der Vliere, Nick Timoney, Izuchukwu and captain Peter O'Mahony completing South Africa's back-row options.
Speaking ahead of the tour, Farrell said: “Touring South Africa and playing a Test series against the defending world champions could not have been a better test for us. It is also a valuable opportunity to continue to grow and develop beyond the Guinness Six Nations.”
“The team will be gathering in Dublin this week for the Tour de France and they know they need to be at their best for the challenge ahead.”
Ireland captain O'Mahony added: “I am honoured to have been asked to lead Ireland in South Africa, one of the toughest challenges in rugby.”
“South Africa, the current world champions, will be our toughest test and we know we will have to perform at a high level to get the results we want. There is a huge amount of respect and familiarity between our two countries at both international and club level following their invitations to play in URC and European Cup competitions in recent years and we know the challenges that await us.”
Ireland squad for South Africa series
Forwards: Ryan Baird, Finlay Bealham, Tadhg Byrne, Caelan Doris, Tadhg Furlong, Cian Healy, Rob Herring, Cormac Izuchukwu, Oli Jaeger, Ronan Kelleher, Joe McCarthy, Peter O'Mahony (captain), Tom O'Toole, Andrew Porter, Cian Prendergast, James Ryan, Dan Sheehan, Nick Timoney, Josh van der Flier.
Bucks: Bundee Aki, Caolin Braid, Craig Casey, Jack Crowley, Ciaran Florey, Robbie Henshaw, Jordan Larmour, James Rowe, Stuart McCloskey, Conor Murray, Calvin Nash, Jimmy O'Brien, Jamie Osborne, Sam Prendergast, Garry Ringrose, Jacob Stockdale.
Absent: Jamison Gibson-Park (hamstring injury), Jack Conan (personal reasons).
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