Ireland head-coach Richie Murphy has been forced to make two changes to his squad ahead of Saturday's under-20 Six Nations opener against Scotland in Cardiff.
Hooker Lee Barron and scrum-half Ben Murphy have both been ruled out of the tournament through injury.
Levi Vaughan and Will Reilly have been called up and will travel with the squad when they depart Dublin on Thursday. The team to face Scotland will be named on Friday afternoon.
Barron and Murphy join hooker Tom Stewart, out-half Cian Whooley and second row Joe McCarthy in being unavailable through injury.
Commenting ahead of the squad's departure for Cardiff, Richie Murphy said: "It is always really unfortunate when a player misses out through injury and it is a double blow to lose Lee and Ben so close to our first game, but it's a great opportunity for the two players coming in now.
"We have prepared really well over a number of five-day camps at the IRFU High Performance Centre and the group is just excited to get over to Cardiff and get stuck into the challenge ahead.
"We know it'll be tough against Scotland but we're looking forward to getting the Six Nations underway."
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