Muhammad Ali's first heavyweight championship fight

Muhammad Ali's first heavyweight championship fight against Sonny Liston is widely considered one of the greatest upsets in boxing history. At the time, Liston was the reigning champion and a fearsome fighter; some boxers were even scared to box him. Ali was a 22-year-old boxer with a brash personality and unorthodox fighting style; at the time, he hadn't changed his name from Cassius Clay to Muhammad Ali yet. The odds were against Clay, peaking at 8-1 against him; this was the worst odds for him in his entire career.

Despite being a heavy underdog, Cassius remained confident in the lead-up to the fight, famously declaring that he would "float like a butterfly, sting like a bee." He also taunted Liston at every opportunity, calling him a "big ugly bear" and predicting he would knock him out in eight rounds.

On the night of the fight, Clay came out strong, using his speed and footwork to avoid Liston's powerful punches. He also landed some impressive shots, including a punch to Liston's eye that caused a cut, the first time Liston had been cut in a boxing match.

In the seventh round, Liston refused to come out of his corner, claiming that he had injured his shoulder. Ali was declared the winner by technical knockout, and the boxing world was stunned.

Clay's win was a triumph of confidence and perseverance. He refused to be intimidated by Liston's reputation or power, and he never wavered in his belief that he could win. As he famously said after the fight, "I am the greatest! I shook up the world!"