Ryan Elias is set to win his 50th Test cap when Wales take on Argentina in round two of the Nations Championship at the Estadio San Juan del Bicentenario on Saturday (20:10ko).
The Carmarthen hooker, who is named among the replacements, is one of six Scarlets selected in the match-day 23 to take on Los Pumas.
Sam Costelow gets the nod at fly-half and Ellis Mee replaces Louis Rees-Zammit on the wing; the pair joining Blair Murray and centres Eddie James and Joe Hawkins in the starting XV.
On Elias’s milestone for Wales, Tandy said: “Ryan’s story is an incredible one. He’s an outstanding leader, an outstanding person more importantly but then I think he’s really added value to our group. It’s an unbelievable achievement to get 50 caps. It’s an honour that’s really deserved.”
Also among the replacements is Exeter’s Kane James, who is poised to make his senior international debut.
Wales are looking to build on last weekend’s impressive win over Fiji in Cardiff.
Tandy added: “There are three changes this week. I think it’s a great opportunity for those boys coming in, an exciting challenge. It’s going to be an amazing opportunity for us playing away from home, which is always exciting. I think it’s a really good test for us to see where we’re at. We know that Argentina are a really passionate and skilful team.”
Wales team to face Argentina in San Juan, Saturday 11 July, KO 20:10h BST. Live on ITV and S4C
15 Blair Murray (Scarlets – 17 caps); 14 Ellis Mee (Scarlets – 9 caps), 13 Eddie James (Scarlets – 10 caps), 12 Joe Hawkins (Scarlets – 12 caps), 11 Josh Adams (Cardiff Rugby | Caerdydd – 71 caps); 10 Sam Costelow (Scarlets – 21 caps), 9 Tomos Williams (Saracens | Saraseniaid – 73 caps); 1 Rhys Carre (Saracens | Saraseniaid – 29 caps), 2 Dewi Lake (Captain, Gloucester Rugby | Caerloyw – 32 caps), 3 Dillon Lewis (Dragons | Dreigiau – 58 caps), 4 Ben Carter (Dragons | Dreigiau – 20 caps), 5 Adam Beard (Montpellier – 66 caps), 6 James Botham (Cardiff Rugby | Caerdydd – 22 caps), 7 Jac Morgan (Gloucester Rugby | Caerloyw – 25 caps), 8 Aaron Wainwright (Leicester Tigers | Caerlŷr – 68 caps)
Replacements: 16. Ryan Elias (Scarlets – 49 caps), 17. Nicky Smith (Sale Sharks – 64 caps), 18. Ben Warren (Ospreys | Gweilch – 1 cap), 19. Teddy Williams (Cardiff Rugby | Caerdydd – 8 caps), 20. Kane James (Exeter Chiefs | Caerwysg – uncapped | heb gap), 21. Kieran Hardy (Ospreys | Gweilch – 31 caps), 22. Max Llewellyn (Gloucester Rugby | Caerloyw – 11 caps), 23. Louis Rees-Zammit (Bristol Bears | Bryste – 41 caps).