A kickoff is a way of starting or restarting play. It occurs at the start of the match, after scoring a goal, at the start of the second half of the match, or at the start of each period of extra time. A score may be made directly from the kickoff. The procedure includes: All players in their own half of the field, opponents of the team taking the kickoff being at least 9.15 meters (10 yards) from the ball until it is in play, the ball being stationary on the center mark, and the referee giving a signal