7. Muhammad Ali and the Phantom Punch
In February 1964, Cassius Clay (he converted to Islam and changed his name to Muhammad Ali the next day) beat heavyweight champ Sonny Liston. The result was so controversial (Liston, claiming a shoulder injury, refused to come out for the seventh round) that a rematch was soon scheduled. In that second bout, an undetectable "phantom" punch sent Liston to the canvas in the first round. Although Liston publicly denied it, it has been speculated that he bet against himself to get out of debt with the Mob or that he was threatened by Muslim extremists who supported Ali.