Morgan was outstanding in Wales’ Junior World Championship campaign in Argentina and is one of a number of talented youngsters named in the home line-up with Scarlets Academy backs Harri Doel and Osian Knott featuring behind the scrum.
New recruit Alex Jeffries, who has signed from the Ospreys, is given his first run-out at tight-head prop, while Steff Thomas, now fully recovered from a knee injury, wears the No. 1 jersey.
The Scarlets currently have 17 players away on international duty, while the remainder of the senior squad were involved in an internal match at Parc y Scarlets on Friday.
Scarlets head coach Richard Kelly, who will be assisted by Paul Fisher and Richie Pugh for the competition, said: “With the amount of players we have in the national team, there are players stepping up to the senior group which creates more opportunities for other players to show they can perform at this A-team level.”
All season ticket holders for 2019-20 can get free entry to all home games in the Celtic Cup.
Scarlets A side to take on Ulster A, Llandovery, Saturday August 24, KO 14:30
15 Kallum Evans, 14 Morgan Griffiths, 13 Osian Knott, 12 Rhodri Jones, 11 Harri Doel, 10 Ioan Hughes, 9 Efan Jones, 1 Steff Thomas, 2 Dom Booth, 3 Alex Jeffries, 4 Robin Williams, 5 Lee Taylor, 6 Stuart Worrell, 7 Jac Morgan (capt) , 8 Lewys Millin
Replacements; 16 Kemsley Mathias, 17 Greg George, 18 Llyr Green/ Jamie Hughes, 19 Lewis Ellis Jones, 20 Gethin Davies, 21 Dafydd Land, 22 Jac Wilson, 23 AN Other.
Ulster A: 15 Conor Rankin, 14 Ethan McIlroy, 13 Hayden Hyde, 12 Ben Power, 11 Graham Curtis, 10 Bruce Houston, 9 Nathan Doak, 1 Callum Reid, 2 Zack McCall ©, 3 Peter Cooper, 4 JJ McKee, 5 Jack Regan, 6 Joe Dunleavey, 7 David McCann, 8 Azur Allison
Replacements; 16 Claytan Milligan, 17 Paul Mullen, 18 Jonny Blair, 19 Connor McMenamin, 20 Matthew Agnew, 21 Aaron Hall, 22 Lewis Finlay, 23 Michael Strong.