List of sports rivalries

A sports rivalry is intense competition between athletic teams or athletes. This pressure of competition is felt by players, coaches, and management, but is perhaps felt strongest by the fans. The intensity of the rivalry varies from a friendly competition on one end to serious violence on the other that, in one case (the Football War), was suggested to have led to military conflicts. Owners typically encourage rivalries as they tend to improve game attendance and television ratings for rivalry matches, but a rivalry that gets out of control can lead to fighting, hooliganism, rioting and some, with career-ending or even fatal consequences.

Rivalries stem from various sources. Simple geographic proximity as well as frequent meetings in important games can lead to rivalries. Games between two rivals of close geographical proximity are usually called a local derby, or simply just derby (UK: /ˈdɑːrbi/; DAR-bee or US: /ˈdɜːrbi/; DER-bee); a sporting fixture between two teams from the same town, city or region, particularly in association football. The phrase most likely originated from The Derby, a horse race in England, founded by the 12th Earl of Derby in 1780, since at least as early as 1840 'derby' has been used as a noun in English to denote any kind of sporting contest.

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