Matthew S. "The Hammer" Hamill (born on October 5, 1976 in Cincinnati, Ohio, United States) is an American wrestler and mixed martial arts (MMA) fighter. He was a three-time NCAA Division III National Champion in wrestling (167 lb. class in 1997, 190 lb. class in 1998, and 197 lb. class in 1999) while attending the Rochester Institute of Technology (RIT) in Rochester, New York. Matt also has a silver medal in Greco-Roman wrestling and a gold medal in freestyle wrestling from the 2001 Summer Deaflympics.

Hamill was a contestant on the third season of The Ultimate Fighter reality television show, training under Tito Ortiz in the 205 lb (93 kg) weight class. He won a preliminary fight against Mike Nickels via decision, but was unable to continue into the semi-finals due to injuries. On June 24, 2006, Hamill fought fellow contestant Jesse Forbes at The Ultimate Fighter 3 Finale on Spike TV and won via TKO.

Hamill then defeated The Ultimate Fighter 2's Seth Petruzelli via unanimous decision at Ortiz vs. Shamrock 3: The Final Chapter on October 10, 2006. Judges scored the bout 29-28, 30-27, and 29-28 for Hamill.

Hamill then fought Rex Holman at UFC 68: The Uprising where he won by TKO in the first round.

Hamill fought Michael Bisping at UFC 75 in London, England on September 8th, 2007, where he lost via split decision. The decision was considered controversial by virtually everyone who has seen the fight. Hamill pushed the pace and took Bisping down numerous times in the first and third rounds and literally had to chase Bisping around the octagon. Many believe Hamill won the fight by winning 2 out of the 3 rounds yet one judge scored 29-28 for Bisping, another 30-27 for Hamill and the spilt decision of 29-28 for Bisping as the winner. This fight is used as a prime example as to encourage fighters not to let the fight go to the judges. A rematch was scheduled for UFC 78, but due to knee surgery Hamill withdrew. A rematch has become unlikely now that Bisping has dropped down to the middleweight division after his fight with Rashad Evans.

Hamill next fought Tim Boetsch on April 3rd, whom he defeated in the second round by TKO, bringing his record to 4 wins and 1 loss. During the fight, Matt suffered a badly split bottom lip due to a knee strike.

Hamill then went on to UFC 88 and fought former UFC Middleweight Champion Rich Franklin as the co-main event. He lost the fight by TKO after a kick to the liver at 0:39 of the third round.

In his latest bout at UFC 92, Hamill defeated Reese Andy in the second round by TKO due to strikes.