A traditional game played under the rules of the Canadian Lacrosse Association
consists of three periods of 20 minutes each (similar to ice hockey),
with the teams changing ends each period. The NLL plays four 15-minute
quarters rather than three periods. If the game is tied at the end of regulation play, a 5-minute overtime (15 in NLL) can be played. Overtime may or may not be sudden victory, depending on the league.