Substitutes on the bench that take over when the starters get tired?...

A player who is disqualified may be substituted with another player after two minutes. If a player assaults a referee, an opponent or any other person severely and deliberately, the referee can expel the player forming a cross over his head with his arms, which will tell the player that he/she will have to leave the game completely and can not be substituted for the rest of the game.

http://en.wikipedia.org/wiki/Handball