Overview
The distance, in boxing, refers to the full number of rounds in a match. It is frequently used in the expression "going the distance", which means fighting a full bout without being knocked out.
In title fights, this is called "the championship distance", which once was 15 rounds but today usually means 12 rounds (See history section), though there were some ten-round championship matches. Non-title fights can be of any length under 12 rounds but are typically 10 rounds or fewer. Women's championship boxing is ten rounds or fewer, each round lasting 2 minutes instead of 3 for men.
History
In the early days of bare-knuckle boxing, there was no limit on the number of rounds and so matches would be fought to a conclusion (i.e. with a knockout or tap out). For example, the match between Simon Byrne and James 'Deaf' Burke in 1833 lasted 3¼ hours.
Subsequently, laws and rules were passed to prevent such protracted bouts. When John L. Sullivan made boxing under Queensbury rules with gloved hands popular, his matches were of a pre-determined length and the referee would decide the winner if they went the distance. If a match reached the prescribed limit without a formal result then the result would be "no-decision", though one boxer might be considered the winner by popular acclaim—a "newspaper decision". To regulate such results better, official judges were appointed to award points so that a technical winner could be determined. For a period, titles in many US states could not be lost if the match went the distance.
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