While Tyson's June 1998 rematch with Evander Holyfield was one of the most anticipated match-ups in boxing history, it quickly became apparent that the boxer had bitten off more than he could chew.
Trailing after two rounds, Tyson decided to take matters into his own ... mouth. When Holyfield danced in during round three, Tyson grasped him, bit off a piece of his ear and spit it on the mat. (You can see it at about 2:40 in the video). The shocked referee neglected to disqualify Tyson from the match, docking him two points as blood streamed down the side of Holyfield's face. That should have been the end. Or at least it would have been for anyone else. When Holyfield left his corner, however, Tyson grabbed him again and bit the other ear.
Promptly disqualified, Tyson would go on to temporarily lose his Nevada boxing license for the incident. Worse still was the damage to his reputation. Tyson was unrepentant, though, saying he'd do it again and that he was merely protecting himself from Holyfield's head butts. Most, however, saw it as Tyson finally hitting rock bottom in his seemingly unstoppable fall from the heavyweight heights.