Takedown and Kimura with Matt ' The Terror" Serra

Serra won first place at the Brazilian jiu-jitsu Pan American games in 1999 and won third place at the 1999 World Championships in Brazil in the brown belt division. Continuing his Martial Arts career, he competed in the ADCC Submission Wrestling World Championship choking out Takanori Gomi, winning a decision over Jean-Jacques Machado, and placing 2nd in the 66--76 kg division. Serra was invited to compete in Pride 9 against Johil de Oliveira but the bout was called off at the last minute when Oliveira was burned in a pyrotechnics accident backstage. Soon after, Matt began to compete in the UFC organization where he built up a record of four wins and four losses. One of the losses was a close decision fight with future Welter and Lightweight champ B.J. Penn which would have earned him a title shot in the failed Lightweight tournament.

The Ultimate Fighter

Matt later became a participant in The Ultimate Fighter 4: The Comeback on SpikeTV. On the show, Serra defeated Pete Spratt and Shonie Carter to reach the finals, his win against Carter avenging his infamous highlight-reel KO loss to Carter at UFC 31. On November 11, 2006, Serra defeated Chris Lytle by split decision to become the Ultimate Fighter 4 Welterweight Tournament Champion.

His win earned him a guaranteed title shot against Georges St-Pierre for the UFC Welterweight Championship, as well as a $100,000 contract and $100,000 sponsorship with Xyience.

Winning the title

Serra fought St-Pierre on April 7, 2007 at UFC 69, and won the UFC Welterweight title via TKO at 3:25 of the first round. Prior to the fight Serra was considered a substantial underdog and consequently the fight is considered to be one of the biggest upsets in MMA history.

The Ultimate Fighter coach

Serra coached season 6 of The Ultimate Fighter reality show with Matt Hughes. Team Serra finished 6--2 in the first round of fights, winning six consecutive times which gave Serra the right to pick the fights in the second round. However, from then on Serra did not corner a single fighter to victory and saw all his trainees eventually lose out. The finale saw Team Hughes fighters Tommy Speer and Mac Danzig face each other for the title of Ultimate Fighter.

Serra said in season 6 of The Ultimate Fighter reality show that Joe Scarola lost his job at Serra's jiu-jitsu school for quitting The Ultimate Fighter within the first week of the show. In exchange, Scarola opened his own academy which has created a feud among the two former friends. Relieving Scarola from his duties was difficult for Serra as the two were close friends, with Scarola serving as best man at Serra's wedding.

The two coaches were scheduled to face off for the UFC welterweight title at the conclusion of the series on UFC 79. Serra, however, was forced to withdraw from the fight due to a herniated disc in his lower back. The injury became evident when Serra was demonstrating a move to his student and fell to the floor in excruciating pain. In Serra's place, Georges St-Pierre fought and defeated Matt Hughes for what was then the interim UFC welterweight title. This led to Serra holding the welterweight title while St-Pierre held the interim title.

After St-Pierre vs Hughes at UFC 79, Serra confirmed to NBC Sports that his back was rapidly improving. He announced that he was scheduled to fight Georges St-Pierre at the first event to take place in Canada, UFC 83. This match would unify the interim and regular welterweight belts.
Serra and his brother Nick run two Brazilian jiu-jitsu schools at local strip malls in Levittown and Huntington, New York. Serra currently trains with Ray Longo and trains fighters such as current UFC middleweight champion Chris Weidman, Pete Sell, Luke Cummo, and Ultimate Fighter Live Finalist Al Iaquinta. They fight under the Serra/Longo Competition Team.