Dragons centre Aneurin Owen will play no further part in the World Rugby U20 Championship after being ruled out of action with concussion.
The 18-year-old was named in the starting XV for Wales U20s first game of the pool stage against hosts Argentina U20 last week, lining up at outside centre with Tiaan Thomas-Wheeler getting the nod at inside centre.
However, his tournament was over inside three minutes as on his first carry he collided heads with an Argentinian defender and remained motionless on the ground.
There was some concern for Owen as he was treated on the field for sometime, however he was able to walk off and has subsequently sat an A-Level exam out in South America, but will not be fit enough to take the field again this summer.
His place in the squad has been taken by Cardiff Blues back-rower Ioan Rhys Davies, who will provide cover for Iestyn Rees, Tommy Reffell and Jac Morgan, with another Dragon, Lennon Greggains, also struggling with a shoulder injury picked up in that first game.
Wales U20 have beaten Argentina but lost to France so far in the pool stage, with Fiji the remaining game to be played on Wednesday evening, a 5pm kick-off UK time. Head coach Gareth Williams is expected to confirm his starting XV on Tuesday evening.