Huddersfield academy player Ronan Costello, 17, has died in hospital, the Giants have announced.
The centre or second row forward had been on a life support machine since being airlifted to Leeds General Infirmary after being hurt playing for Huddersfield in an Under-19s game against Salford on Saturday.
The match was abandoned after the freak accident.
A statement by the Super League club said: "It is with regret that Huddersfield Giants wish to inform everyone of the passing of 17-year-old academy player Ronan Costello today.
"Ronan was airlifted to the LGI on Saturday afternoon after he was injured during the Giants academy game with Salford.