
11. Rocky Marciano
No list of greatest fighters could be complete without Rocky Marciano. ‘The Brockton Blockbuster’ remains the only heavyweight champion to have retired undefeated as a champion. He had a record of 49-0 and his knockout-to-win percentage of 87.76% remains one of the best in the history of the division.

He held the title for four years from 1952-1956 defending it six times with success. Marciano’s punching power, chin, speed, and ferocity all marked him out as a special force of nature during his remarkable era. His legacy was a major influence behind the Rocky Balboa film series.