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Mike Tyson is restrained after knocking down Michael Spinks in their fight.

Mike Tyson KO1 Michael Spinks, June 27, 1988 – This fight was Tyson at his peak, as he terrorized a petrified Spinks. It was a matchup of two unbeaten men holding heavyweight belts, but Spinks was battered around until Tyson stopped him. Tyson decked Spinks with a right to the body about 70 seconds into the fight. Spinks got up, but Tyson went right after him and quickly knocked him out with a short right hand.