For UEFA Euro 2016, the 24 participating national teams must submit squads of 23 players – of which three must be goalkeepers – by 31 May 2016, 10 days prior to the opening match of the tournament. In the event that a player on the submitted squad list suffers an injury or illness prior to his team's first match of the tournament, that player may be replaced, provided that the team doctor and a doctor from the UEFA Medical Committee both confirm that the injury or illness is severe enough to prevent the player's participation in the tournament.