Scarlets prop Harri O'Connor has been called up to the Wales squad for the three-Test tour of South Africa.
O'Connor, 21, has been added to the party travelling later this week as cover for Tomas Francis, who has a back niggle.
O'Connor is the second uncapped tight-head called up this month by Wayne Pivac.
Saracens front rower Sam Wainwright replaced the injured Leon Brown in what is now a 34-man squad.
Francis and Dillon Lewis are the other specialists included.
O'Connor's fellow Scarlets prop Samson Lee is sidelined with an Achilles injury while another colleague, WillGriff John, has not been called up.
Pivac revealed Francis has been managing a back injury but believes the Ospreys prop will be fit for the first Test on 2 July.
"We expect him (Francis) to be fully fit for the first Test but it's just a precaution to make sure we have the numbers we need to get through," said Pivac.
"Tomas has just picked up a niggle in his back so it's been a bit of a problem for him on and off in the season.
"We are just treating that with care so it's just a precautionary measure to make sure we have the numbers in training and we can prepare as we need to."
O'Connor has played in only nine competitive games since making his debut against Ospreys on 1 January, 2022.
He started that game, which was followed by eight replacement appearances.
O'Connor had been part of the Bath academy and graduated through the Welsh Exiles programme before signing for Scarlets.
He is Welsh qualified through his father, who hails from Bonymaen. O'Connor studied at Llandovery College before playing for Wales Under-18s and Under-20s.
He gained experience in the English Championship with Nottingham in the 2020-21 season and also played in a friendly for Scarlets against Dragons before making his competitive debut.
The inclusion of O'Connor and Wainwright takes the number of uncapped players in the squad for South Africa to four, with Leicester flanker Tommy Reffell and Cardiff number eight James Ratti making up the quartet.
"Harri is one of number of young players across the positions in the game we are keeping an eye on," said Pivac.
"We have spoken to the guys at the Scarlets and they speak highly of him in terms of where he is at in his game currently and where he can get to in the future.
"He is one we think will benefit by being part of this trip."
On having two uncapped young props in the squad, Pivac added: "It's always a concern if things don't go well, but there is also the opportunity for young players to learn a hell of a lot and grow.
"There is no better learning [experience] than going up against the best in the world in any sport, and at the moment, you would have to say the South Africa scrum has probably shown it has consistently been the best in the world.
"They are not world champions for nothing. [They] are very good at what they do, so if you are a young guy going on tour and coming up against that, you are going to learn a lot. It's an exciting time for any youngster going on a tour like this."
Pivac said he is confident Cardiff duo Tomos Williams and Josh Adams will be fit for the trip after missing the finish of the 2021-22 season through injury.
Captain Dan Biggar will link up with the squad on Thursday alongside the other England-based players.
Biggar has recovered from a back injury suffered in Northampton's Premiership play-off semi-final defeat to Leicester earlier this month.
"He's had a good break and his medical team has done a good job with him," added Pivac.
"The reports to us have been virtually daily from Dan himself. He's in good spirits and he'll be fine to go."
The opening Test between Wales and South Africa is in Pretoria, with the other two games on subsequent Saturdays in Bloemfontein and Cape Town respectively.
Wales squad for South Africa
Forwards (20): Rhys Carre, Wyn Jones, Gareth Thomas, Ryan Elias, Dewi Lake, Sam Parry, Tomas Francis, Dillon Lewis, Harri O'Connor, Sam Wainwright, Adam Beard, Will Rowlands, Alun Wyn Jones, Ben Carter, Dan Lydiate, Josh Navidi, James Ratti, Taulupe Faletau, Taine Basham, Tommy Reffell.
Backs (14): Gareth Davies, Kieran Hardy, Tomos Williams, Dan Biggar (capt), Gareth Anscombe, Rhys Patchell, George North, Nick Tompkins, Owen Watkin, Johnny Williams, Josh Adams, Alex Cuthbert, Louis Rees-Zammit, Liam Williams.