[14] After high school, he attended Iowa Central Community College, wrestling for one season (2001–02) and winning the NJCAA National Championship in the heavyweight (285 lb limit) division.

While at ASU earning All-American status twice, Velasquez wrestled alongside future UFC fighters Ryan Bader and C.B.

[21] Velasquez made his MMA debut on October 7, 2006, against Jesse Fujarczyk at Strikeforce: Tank vs. Buentello, he won by TKO in the first round.

[25] His next opponent was expected to be Shane Carwin[26] with the winner likely challenging for the UFC Heavyweight Championship held by Brock Lesnar.

[40] However, Mir was moved up to face Junior dos Santos after Alistair Overeem was suspended for elevated testosterone levels.

It is widely thought that White made the decision to have the rematch with Dos Santos at such an unexpected time as both fighters were injured going into their first fight.

[44] In the rematch, Velasquez defeated Dos Santos in a dominant performance[45] via unanimous decision (50–45, 50–43, and 50–44) to regain the UFC heavyweight title.

[51][52] However, on October 21, 2014, Velasquez pulled out of the bout due to a torn meniscus and sprained MCL in his right knee, and was replaced by Mark Hunt.

[56] Velasquez would later admit that he had not adequately prepared for the fight, held in Mexico City which sits at an altitude of 7,300 feet, as he had only moved his camp to elevation two weeks before the day of the card.

[57] A rematch with Werdum was expected to take place on February 6, 2016, at UFC Fight Night 82 until both fighters backed out citing injuries.

[61] However, the Nevada State Athletic Commission failed to approve Velasquez to fight, determining after physical examinations and interviews that he was unfit to compete due to bone spurs on his back.

He moves forward constantly, giving opponents very little room to land clean strikes, all while utilizing powerful and extremely swift punching combinations.

[68] If Velasquez knocks his opponent to the ground during a fight, he often uses grappling skills to maintain a dominant position while he continues to strike from above.

[69] Velasquez was often praised for his cardiovascular training; he had tremendous endurance that allowed him to continue to fight aggressively after his opponents became exhausted, earning him the nickname "Cardio Cain".

On July 19, 2018, it was reported that he trained in the WWE Performance Center under head coach Norman Smiley and later attended Diamond Dallas Page's yoga session.

[71] In March 2019, Velasquez signed a multi-match agreement with Mexican professional wrestling promotion Lucha Libre AAA Worldwide as a heavyweight competitor.

Velasquez made his debut for the promotion at Triplemanía XXVII in a trios match, teaming with Cody Rhodes and Psycho Clown to face Texano Jr, Taurus, and Killer Kross.

[72] Velasquez's debut surprised many fans, as he donned a luchador mask throughout the whole match and displayed many athletic moves, such as using a hurricanrana.

[73] Velasquez competed in his second and final AAA match at Lucha Invades NY, where he teamed with Brian Cage and Psycho Clown to defeat Rey Escorpión, Texano Jr., and Taurus.

[74] On October 4, 2019, on the first episode of SmackDown on Fox, which was also the show's 20th Anniversary, Velasquez made his WWE debut, accompanied by Rey Mysterio, coming out to confront and eventually attack Brock Lesnar after his WWE Championship victory as a measure of revenge for Lesnar attacking Mysterio and his son, Dominik, earlier in the week.

[77] In January 2020, WWE had planned to use Velasquez at their Royal Rumble pay-per-view event, but he suffered an injury and the idea was scrapped.

Nine days later on October 18, it was announced that Velasquez would team with Psycho Clown and Pagano to face Los Mercenarios (Rey Escorpión and Taurus) and a mystery partner at Triplemanía Regia II.

On December 3, 2022, Velasquez made his return to AAA, teaming with Pagano and Blue Demon Jr. to defeat La Empresa (Sam Adonis and Gringo Loco) and Taurus at an event held at the Mullett Arena on the campus of his alma mater Arizona State University.

[82] In addition to his Spanish-language TV appearances, he was also a featured guest on the TBS late night show Lopez Tonight.

[89][90] On February 28, 2022, Velasquez allegedly shot at a man in Santa Clara County, California, and hit an unintended victim.

The man whom Velasquez allegedly intended to shoot, Harry Goularte Jr., had been arrested prior to the shooting for allegedly committing child sexual abuse on Velasquez's son at a daycare owned by Goularte's family, and was later released from custody on a personal recognizance bond.

[93] Velasquez was later arrested and booked into the Santa Clara County jail on an attempted first-degree murder charge.

[106] On November 22, Velasquez was granted permission from the court to travel to Tempe, Arizona, to partake in a Lucha Libre AAA Worldwide professional wrestling event.

[111] The lawsuit was filed also against Goularte's mother and stepfather who operate the child-care business where the alleged sexual abuse took place.

[103] In June 2022, Goularte plead not guilty to related criminal charges, and after multiple continuations during the following year, the trial-setting hearing was set to take place on August 30, 2023.