Retired numbers in football (soccer)

Association football clubs around the world sometimes retire squad numbers to recognise players' loyal service, sometimes as a memorial after their death.

This practice, long established in the major North American sports, is a recent development in football since squad numbers for specific players were not widely used until the 1990s. Before then, it was typical for players in the starting lineup to be issued numbers 1 to 11 by formation/position on a match-by-match basis, and substitutes to be numbered from 12 upwards, meaning a player might wear different numbers during the season if they were to play in different positions for tactical reasons, or simply not be a regular in the starting lineup.

Retiring a player's number usually occurs after the player has left the team or retired. It honours a player who has meant so much to his club that they retire the shirt number that the player wore during their time there, meaning no other player is permitted to use that number in the future. In some cases, such as those of Jason Mayélé, Vittorio Mero, Marc-Vivien Foé, Miklós Fehér, Ray Jones, Dylan Tombides, François Sterchele, David di Tommaso, Antonio Puerta, Besian Idrizaj and Piermario Morosini, numbers have been retired to posthumously honour a player who died while still active. Also, Norwegian club Fredrikstad retired Dagfinn Enerly's number following an on-pitch accident that left him paralysed. In Britain, only Bobby Moore's and Jack Lester's shirt numbers have been retired due to great service to the club as opposed to a tragic incident. Although it has not been officially retired, Gianfranco Zola's No. 25 shirt has not been reissued by Chelsea since he left the club in 2003.

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