 American and Canadian sports leagues typically have such playoff systems.These have their roots in long travel distances common in U.S. and Canadian sports; to cut down on travel, leagues are typically aligned in geographic divisions and feature unbalanced schedules with teams playing more matches against opponents in the same division.Due to the unbalanced schedule typical in U.S. and Canadian leagues, not all teams face the same opponents, and some teams may not meet an even number of times during a regular season, if at all.