London - Ross Moriarty, a double Under-20 World Cup-winner with England, was one of four uncapped players selected by Wales to face Ireland in Saturday's World Cup warm-up in Cardiff.
The Gloucester flank, 20, was joined by wing Eli Walker, centre Tyler Morgan and lock Dominic Day in the team announced by head coach Warren Gatland on Tuesday.
The fixture at the Millennium Stadium follows intensive training camps in Switzerland and Qatar and is the first of three warm-up games building up to Wales's opening World Cup game against Uruguay on September 20.
"Saturday is a real opportunity for these players to put their hand up," said Gatland in a press release issued by the Welsh Rugby Union.
"We have been really impressed over the last few weeks. We have put the players under a lot of pressure, and they have responded really well.
"This is their opportunity to show what they can do on the international stage. We have the right blend of youth and experience, and it's all about grasping the chance at this level.
"It's going to be a huge occasion - Ireland coming to town, a packed Millennium Stadium and players with everything to play for."
Moriarty helped England win the Under-20 World Cup in 2013 and 2014, but subsequently decided to follow in the footsteps of his father Paul and uncle Richard by playing for Wales.
There are also two uncapped players among the replacements in the shape of New Zealand-born fly-half Gareth Anscombe and his Cardiff Blues colleague Kristian Dacey.
Scarlets centre Scott Williams will captain Wales for the first time.
Wales will play Ireland in a return fixture in Dublin on August 29 before welcoming Italy to the Welsh capital seven days later.
As well as Uruguay, Gatland's men have also been drawn alongside England, Australia and Fiji in Pool A at the World Cup.
Gatland will announce his final 31-man squad for the tournament later this month.
15 Hallam Amos, 14 Alex Cuthbert, 13 Tyler Morgan, 12 Scott Williams (captain), 11 Eli Walker, 10 James Hook, 9 Mike Phillips, 8 Dan Baker, 7 Justin Tipuric, 6 Ross Moriarty, 5 Dominic Day, 4 Jake Ball, 3 Aaron Jarvis, 2 Richard Hibbard, 1 Nicky Smith
Substitutes: 16 Rob Evans, 17 Kristian Dacey, 18 Scott Andrews, 19 James King, 20 Taulupe Faletau, 21 Lloyd Williams, 22 Gareth Anscombe, 23 Matthew Morgan