Cain Ramirez Velasquez (born July 28, 1982) is an American mixed martial artist fighting in the Ultimate Fighting Championship where he is a former UFC Heavyweight Champion. He is a two-time All-American collegiate wrestler from Arizona State University in Tempe, Arizona, and a Junior College National Champ at Iowa Central Community College. He is a two-time 5A state champion in Arizona, compiling a record of 110–10 for Kofa High School in Yuma, Arizona. Cain began his mixed martial arts career right after college, joining American Kickboxing Academy. Velasquez is a brown belt in Guerrilla Jiu-Jitsu and a NCAA Division I Wrestler. He has notable wins over Cheick Kongo, Ben Rothwell, Antônio Rodrigo Nogueira and Brock Lesnar.
Velasquez made his UFC debut against Brad Morris at UFC 83 and won due to strikes in the first round. In his next fight, Velasquez defeated Jake O'Brien at UFC Fight Night 14 by TKO in round one. Velasquez then faced Denis Stojnić at UFC Fight Night 17 and the fight was stopped in round two with Velasquez earning the victory by TKO. Velasquez also earned Knockout of the Night honors for his performance. Velasquez's next fight was in UFC 99 against former kickboxer and established UFC heavyweight Cheick Kongo. Velasquez was once again dominant, landing 251 strikes and winning the bout by unanimous decision (30–27 on all cards).
His next opponent was expected to be Shane Carwin with the winner likely challenging for the UFC Heavyweight Championship held by Brock Lesnar. However that bout was scrapped and Velasquez was instead told he would be fighting Ben Rothwell at UFC 104. He defeated Rothwell by second round TKO.
Velasquez faced former Pride Heavyweight Champion and former UFC Interim Heavyweight Champion Antonio Rodrigo Nogueira on February 20, 2010 at UFC 110. Going into the fight, some commentators predicted that Nogueira would take the victory due to a supposed lack of striking power for Velasquez. They were proven wrong when Velasquez defeated Nogueira via first round knockout, earning Knockout of the Night honors
Dana White announced via SportsNation that the UFC would be bringing back UFC Primetime to promote Lesnar vs. Velasquez. Velasquez defeated Brock Lesnar for the UFC Heavyweight Championship via TKO in the first round, earning Knockout of the Night honors.
Velasquez suffered a torn rotator cuff in his right shoulder during his fight with Lesnar at UFC 121 and was expected to be sidelined for at least 6–8 months. Surgery on the shoulder was successful and Velasquez planned to return as early as Fall 2011.
Velasquez was expected to make his first title defense against Junior dos Santos, with a target date of November 19, 2011 at UFC 139, but the fight was later moved to November 12, 2011 to headline the first UFC on Fox 1.
Velasquez suffered his first, and to date, only loss via KO (punches) at 1 minute and 4 seconds of the first round at the hands of then title contender, Junior Dos Santos. Consequently, he lost the UFC heavyweight championship belt to Junior Dos Santos.
Velasquez is expected to face Frank Mir on May 26, 2012 at UFC 146 in a number 1 contender's match for the UFC Heavyweight Championship.