10 of the best boxers of all time

4. Rocky Marciano

Rocky Marciano is one of history's only undefeated heavyweight champions. With a nearly unmatched 49-0 professional record coupled with 43 knockouts, Marciano was the undisputed champion from 1952 until his retirement in 1956. His knockout-to-win ratio is still among the highest for all fighters in history.

Born of Italian heritage to a family in Brockton, Massachusetts, Marciano was an exceptionally athletic youth. He was not only a talented boxer, but played baseball and football throughout his school years, and even tried out for the Chicago Cubs baseball team after serving in the army.

Boxing proved to be his true calling though and after a successful amateur career as well as impressive showings in Army tournaments in the late 1940s, Marciano committed to professional fighting. This of course would be the right decision as he went on to have a hall-of-fame career defeating tough contemporaries like Archie Moore, Jersey Joe Walcott, and even the legendary Joe Louis.

Known for his power punching, Marciano holds the distinction of stopping every man he beat in heavyweight title fights. He had relentless stamina and an iron chin that helped him stay strong through long fights and return as much punishment as he absorbed.

As one of the most influential and prolific boxers of his era, Marciano certainly established himself as one of the best boxers ever.