"Free substitution" rules for Under 19 and Under 16

Players who have completed the mandatory two-playing-period-per-game within the first three periods of the game may participate in a free substitution system during the fourth period. Under this system, substitution will be allowed only upon stoppage of play for a throw-in by the team wishing to make the substitution, or for any goal kick or kick-off; substitution is not allowed on a corner kick, penalty kick, or free kick. The substitution will not be valid unless the consent of the referee on the field is obtained. Players must enter the field at the halfway line. Players leaving the game must exit by the nearest sideline to minimize disruption of play on the field. Players are expected to be off the playing field within 15 seconds of the approval by the referee to allow the substitution to take place.

Players who have not played their two full periods will remain in the game and will play the full fourth period. These non-substitution-eligible players must be identified to the referee prior to the start of the fourth period by the coach or team captain. They may only be removed from the field for injury with the consent of the referee.

Removal of players from the game by substitution who have not completed their mandatory two game periods is grounds for forfeiture of the game by the team violating the two-periods rule.