Undefeated heavyweight world champion, Boxing

According to Official Guinness Records,

Rocky Marciano (USA) (b. Rocco Francis Marchegiano) (1923-69) is the only world champion at any weight to have won every fight of his entire completed professional career, from 17 March 1947-21 September 1955 (he announced his retirement on 27 April 1956);43 of his 49 fights were by knock-outs or stoppages.

For a complete list of Unknown date records, please visit Unknown date Guinness Records in United States.

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