6. Rocky Marciano TKO13 Jersey Joe Walcott, Sept. 23, 1952 – This fight marked the start of Marciano's reign as heavyweight champion. He was far behind on points, but caught Walcott on the chin with a right cross that led to one of the great boxing photos of all-time. The photo showed the punch at the moment of impact, with Walcott's face grotesquely contorted. (Photo credit: Getty)
{}