Undisputed champion

In professional boxing, the undisputed champion of a weight class is a boxer who is recognized as the world champion at that class by each boxing organization.

Prior to the 1960s, most champions were "undisputed", although the term was rarely used (it does not appear in one 1970 Boxing Dictionary). Early boxing champions at various weight divisions were established by acclamation between 1880 and 1920. Once a consensus champion had been awarded the title, the championship could usually be taken only by beating the reigning holder, establishing a lineal championship.

The New York State Athletic Commission (NYSAC) recognized champions from its foundation in 1920. The National Boxing Association (NBA) was founded by other U.S. state bodies in 1921, and began recognising champions in 1927. Until the 1960s, both usually recognised the same lineal champion. However, disputes could arise if the champion retired or moved to a different weight class. Occasionally, the International Boxing Union (renamed the European Boxing Union in 1946) recognised a different champion. The disputes were usually short-lived as a lucrative fight would be organised between the rival champions. The longest split was ten years, of the middleweight title, between Mickey Walker's move up to heavyweight in 1931 and NBA champion Tony Zale's defeat of NYSAC contender Georgie Abrams in 1941. An early use of "undisputed" appears in a New York Times preview of the 1941 fight.

The NBA renamed itself the World Boxing Association in 1962 (later based in Panama), and in 1963 the NYSAC, EBU and other countries formed the rival World Boxing Council, based in Mexico. The number of disputed champions increased in the 1960s and especially in the 1970s. Both bodies established separate official rankings and required champions to face their top-ranked contenders or forfeit their titles. Some of the most highly regarded and lucrative fights were unification bouts between rival champions to create an "undisputed champion".

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