Domestic association football season

The domestic association football season in countries that association football is played around the world varies in length and time of year contested. Most employ a single period in which the main league competition is contested alongside any cup competitions, although many Latin American leagues have two competitions contested in one season under the Apertura and Clausura system.

As a rule, the period of the domestic football season is ultimately dictated by the weather, with most football games played on natural grass pitches which are vulnerable to freezing or becoming water-logged, although advances in artificial turf and pitch drainage/heating systems have improved pitch availability in many leagues.

In countries where association football competes with other football codes that are locally more popular, the season cycle can also be dictated by the scheduling of competing codes. Major League Soccer (MLS), which began in the United States and has since expanded into Canada, has had to compete with American football from its inception, and now competes with Canadian football as well. When MLS began, most of its teams had to play in large American football stadiums that were used by teams in the NFL or college football. This led to scheduling the season to begin in spring and end in fall (autumn), which put the bulk of the season outside that of American football. Stadium conflict has now been reduced with the advent of soccer-specific stadiums. In Australia, the two most popular football codes are Australian rules football and rugby league, both of which are traditionally played in the Southern Hemisphere winter. Because all of the stadiums used by the A-League are also used for one or both of these two codes, that league chose to operate on a spring-to-autumn cycle, which placed most of its season outside those of Australian rules and rugby league.

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