St. Pierre had dreamed of becoming a UFC champion since watching Royce Gracie fight in 1993 at UFC 1. St. Pierre had his first amateur bout when he was only 16 years old. He states, “When I won my first amateur (MMA) fight, I was 16 years old and I beat a guy that was 25. I was only a Kyokushin karate fighter and the guy I fought was a boxer. At the time my ground skills were very poor, I didn’t know nothing on the ground.” St. Pierre won his fight by knockout, going low with several leg kicks and then going high with a kick to the head.

St. Pierre’s pro debut was against Ivan Menjivar and ended in a first round TKO win. St. Pierre went on to win his next three fights before making his TKO debut against Pete Spratt at TKO 14 (November 29, 2003). St. Pierre defeated Spratt with a rear naked choke in the first round.

St. Pierre made his Octagon debut at UFC 46 where he defeated Karo Parisyan by decision. His next fight with the UFC was against Jay Hieron at UFC 48. St. Pierre defeated Hieron via TKO (strikes) in only 1:42.

Hughes (L) St Pierre (R)

Following his second straight win in the UFC, he faced Matt Hughes at UFC 50 for the welterweight title. Despite a competitive performance, St. Pierre tapped out to an armbar with only 1 second remaining in the first round.