Playoff

The playoffs, play-offs, postseason and/or finals of a sports league are a competition played after the regular season by the top competitors to determine the league champion or a similar accolade. Depending on the league, the playoffs may be either a single game, a series of games, or a tournament, and may use a single-elimination system or one of several other different playoff formats. Playoff, in regard to international fixtures, is to qualify or progress to the next round of a competition or tournament.

In team sports in the U.S. and Canada, the vast distances and consequent burdens on cross-country travel have led to regional divisions of teams. Generally, during the regular season, teams play more games in their division than outside it, but the league's best teams might not play against each other in the regular season. Therefore, in the postseason a playoff series is organized. Any group-winning team is eligible to participate, and as playoffs became more popular they were expanded to include second- or even lower-placed teams – the term "wild card" refers to these teams.

In England and Scotland playoffs are used in football to decide promotion for lower finishing teams, rather than to decide a champion in the way they are used in North America. In the Championship (the second tier of English football) teams finishing 3rd to 6th after the regular season compete to decide the final promotion spot to the Premier League.

Evidence of playoffs in professional football dates to at least 1919, when the "New York Pro Championship" was held in Western New York (it is possible one was held in 1917, but that is not known for sure). The Buffalo and Rochester metropolitan areas each played a championship game, the winners of which would advance to the "New York Pro Championship" on Thanksgiving weekend. The top New York teams were eventually absorbed into the NFL upon its founding in 1920, but the league (mostly driven by an Ohio League that did not have true championship games, though they frequently scheduled de facto championship matchups) did not adopt the New York league's playoff format, opting for a championship based on regular season record for its first twelve seasons; as a result, four of the first six "championships" were disputed. Technically, a vote of league owners was all that was required to win a title, but the owners had a gentlemen's agreement to pledge votes based on a score (wins divided by the sum of wins and losses, with a few tiebreakers). When two teams tied at the top of the standings in 1932, an impromptu playoff game was scheduled to settle the tie.

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