February 11, 1990: Mike Tyson was the undisputed heavyweight king of boxing, having successfully defended his title nine times. He held the WBC, WBA, and IBF titles. He was 37-0 and had never really been challenged. And then he ran into 42-1 underdog James "Buster" Douglas (29-4-1) at the Tokyo Dome in Tokyo, Japan. What happened next is best put by commentator Jim Lampley's words: "Let's go ahead and call it. The biggest upset in the history of heavyweight championship fights!"

Douglas was riding a 6-win streak for the chance to face Tyson, and had extra inspiration for the fight as his mom had passed away just 23 days prior. It was rumored Tyson didn't train as hard for the fight, even though he looked fit. He definitely wasn't prepared mentally for the fight or what was about to happen.

Douglas used his 12-inch reach advantage with jabs that Tyson couldn't shake. He also came out aggressive and took the fight to the champ, dominating most of the fight. By the middle rounds, Tyson's left eye was swollen shut.

Tyson came back in the 8th with his signature uppercut that sent Douglas to the canvas. It looked like he may pull out the fight, but Douglas got up after a 9-count. Tyson's camp, and promoter Don King, were livid after the fight, saying the count by referee Octavio Meyran was too slow and allowed Douglas to get up.

That was the only setback for Douglas. Tyson looked stunned, wobbly and defeated. The 10th round saw something no one expected heading into the fight: Mike Tyson being knocked out. A devastating uppercut stopped Tyson in his tracks, and Douglas followed with four punches to the head that knocked "Iron Mike" down for the first time in his career. Tyson fumbled with his mouthpiece and was disoriented as he tried to get up in time, but as he stood Meyran called the fight.

Douglas was the heavyweight champion in shocking fashion. Despite Tyson's desire for a rematch, Douglas never gave him one. Instead he fought the No. 1 contender, Evander Holyfield Jr. and would lose his title. Tyson would fight four more times before throwing away the prime of his career to a rape conviction, in which he did 3 years in prison. He was never the same fighter again.

Here's to you James "Buster" Douglas and the greatest upset in boxing history.

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