Sean Pierson made his Ultimate Fighting Championship debut in Montreal on Saturday December 11, 2010 against Matt Riddle. The fight was an action-packed battle between the two welterweights with Pierson having his hand raised at the end of three rounds with a unanimous decision victory.

UFC president Dana White said that the UFC 124 preliminary bout should have garnered "Fight of the Night" accolades and he "took care of" Riddle and Pierson for their efforts inside the Octagon.

The "Fight of the Night" bonus was voted on by the fans at the UFC's website and they voted for the main event between UFC welterweight champion Georges St. Pierre and Josh Kosheck. St. Pierre and Koscheck each received a bonus of $100,000 after the vote.

Following the event, White said that UFC 124 would be the first and last time that the fans would be allowed to vote on the award as he felt that they rewarded the wrong fighters.

The bonus money that White awarded Pierson may come in handy, as the fight has landed him in trouble with his employer, the Toronto Police Department.

Pierson was recruited by the Toronto Police and was to have his first official duties with the department this week, but those duties have been put on hold.

The Toronto Star reported the following: “Police spokesman Tony Vella did not comment directly on Pierson’s case but said every police officer who has paid 'secondary employment' must first clear it with the force.”

The Star also wrote, "Requests for secondary employment can be denied if it constitutes a conflict of interest."

Pierson's case is currently under investigation by the Toronto Police Department and there is no word on whether he will be forced to chose one career over the other.

For his part, Pierson was understanding of the situation, stating, "I can appreciate the position they’re in with what I do. I don’t look at mixed martial arts as a negative, but I think the mainstream still looks at us as a bit of a black eye."

Pierson has been competing in mixed martial events since 1999 and has compiled a career record of 11-4.