From Mike Tyson's 91-second destruction of Michael Spinks to Joe Louis's politically charged 2-minute demolition of Max Schmeling, the first round is where legends are made and dreams are shattered. Sonny Liston flattened Floyd Patterson in just over two minutes [citation:1][citation:3]. In MMA, Gerard Gordeau's 26-second head-kick knockout at UFC 1 marked the sport's first KO [citation:2][citation:5]. Vitor Belfort leads UFC history with 11 first-round knockouts, while Sergei Pavlovich boasts six consecutive first-round stoppages [citation:7][citation:9]. These are the moments when one punch changed everything—instant, brutal, and unforgettable. Boxing history, UFC knockouts, combat sports, and the art of the early finish.