Sean Sharaf just pulled off one of the greatest upsets and knockouts in UFC history after he blasted Gable Steveson with a single punch to end their fight in just 12 seconds at UFC 331.

As an Olympic gold medalist and a protege of UFC legend Jon Jones, Steveson appeared poised for a huge career in the UFC, but none of that seemed to impress Sharaf. He came after Steveson at every turn in the leadup to this fight and then did it again once the action started on Saturday.

Sharaf wasted no time swinging huge shots at his opponent, and it was ultimately a devastating left hook that twisted Steveson's head around and sent him crashing to the canvas. Referee Frank Trigg rushed in to stop the fight with the end coming at just 12 seconds into the opening round.

"I'm Not Surprised, Motherf*ckers"

"I'm not surprised, motherf*ckers," Sharaf shouted after his monumental win. "I feel amazing. I work so hard. I believed in myself when no one believed in myself. That's it. I know I got the power. I've just got to believe in myself."

Despite stepping into the fight as a massive underdog, Sharaf never seemed to care much about the odds because he showed no fear taking on the 2020 Olympic gold medalist. Sharaf did not really even get to warm up in the fight because he unloaded the fight-finishing shot with his second punch as Steveson crumbled from the knockout blow.

Steveson was quick to leave the Octagon, and it is an upset for the ages as Sharaf gets the win and Steveson falls to 4-1 in his MMA career.