Mike Tyson vs. Buster Douglas

February 11, 1990 HBO Broadcast Tokyo Dome Tokyo, Japan Widely considered the biggest upset in sports history. Douglas entered the fight as a 421 underdog. Tyson would be dominated the entire fight until the 8th round when he knocked Douglas down, leading to the infamous long count controversy. Douglas would recover and eventually score a 10th round KO to capture the undisputed heavyweight championship, handing Tyson his first career loss.