Law 3 – The Number of Players
All Matches
 
  • In all matches, the names of the substitutes must be given to the referee prior to the start of the match. Substitutes not so named may not take part in the match.
Substitution Procedure
  To replace a player by a substitute, the following conditions must be observed:
  • the referee is informed before any proposed substitution is made;

  • a substitute only enters the field of play after the player being replaced has left and after receiving a signal from the referee;

  • a substitute only enters the field of play at the halfway line and during a stoppage in the match;

  • a substitution is completed when a substitute enters the field of play;

  • from that moment, the substitute becomes a player and the player he has replaced ceases to be a player;

  • a player who has been replaced takes no further part in the match;

  • all substitutes are subject to the authority and jurisdiction of the referee, whether called upon to play or not
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