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Sonny Liston

1962-64

Liston was an intimidator whose uncertain age, criminal background and association with the mob forged his identity. The only thing larger than his mystique was his power, which was colossal: "The Big Bear" recorded 39 knockouts in 50 victories, including 23 within the first three rounds.

Liston took the heavyweight world title from Floyd Patterson with an incredible display of power in 1962, and his one-round knockout in the rematch was equally impressive. Liston lost the belt to Muhammad Ali (then Cassius Clay) in 1964, taking a heavy dose of punishment before deciding not to come out of his corner for the seventh round.