[5][6][7] Hunt was born in South Auckland, into a large Samoan family, and was a troubled child eventually leading to two jail terms for violent offending.

[8][9] He had no intention to be a professional fighter until a late night altercation outside a nightclub just after getting out of jail for the second time in Auckland changed the course of his life.

After that he took part of K-1 World GP 2001 in Melbourne, where he beat Japanese boxer Hiromi Amada, before suffering a close unanimous decision loss to reigning champion Ernesto Hoost.

However, because of his exciting fighting style Hunt was granted a wildcard spot in the repercharge tournament for the K-1 World GP 2001 Finals, when Mirko Cro Cop had to pull out due to injury.

Hunt then TKO'd Adam Watt to earn his place in the K-1 World Grand Prix Finals at the Tokyo Dome.

[citation needed] During the matchmaking for the K-1 Finals, Hunt surprised the crowd by choosing Jérôme Le Banner, whom he had just lost in the previous year, as his quarterfinal opponent.

Hunt won the rematch by knocking out Le Banner in the second round and advanced himself onto the semi-finals facing Stefan Leko.

[citation needed] In 2002, Hunt went to Paris to fight Le Banner again for the third time what turned out to be one of the biggest battles in K-1 history.

In quarter finals, entering the third round and behind on all scorecards, Mark was able to connect with a right cross that knocked out Stefan Leko and advanced him to the semi-finals against his career long nemesis Jerome Le Banner.

[citation needed] In April 2008, FEG announced Hunt's return to K-1 and nominated him as the challenger of K-1 Super Heavyweight Championship held by Semmy Schilt.

Hunt stepped in as a late replacement for Sakuraba, and won a split decision against an outweighed PRIDE middleweight (205 lb) champion Wanderlei Silva.

Silva, renowned for his brutal punching and Muay Thai clinch game, was neutralized by the hard-hitting Samoan and knocked down several times in the fight.

At the PRIDE Shockwave 2005 event, Hunt surprisingly defeated Mirko Cro Cop via a split decision, after his earlier loss to him in K-1.

At PRIDE 31: Unbreakable, Hunt defeated Japanese boxer Yosuke Nishijima in the third round with a powerful one-two punch.

He then faced American catch-wrestler Josh Barnett at PRIDE Critical Countdown Absolute in the second round of the tournament.

Photos that had emerged on the internet had shown that Hunt had lost a considerable amount of weight in comparison to that of his Pride days.

[31][32] Post-fight, Dana White stated that the bout won Fight of the Night and, despite the draw result, both men would receive their win bonuses.

[37] At first, Hunt blamed his tweets on hunger, but later in mid-August he revealed that he had decided to walk away from the sport due to business reasons.

[46][47] Miocic set a UFC record for the most strikes landed in a fight, outlanding Hunt 361 – 48 over the duration of the bout.

[58] The test result was conducted on 28, 11 June days prior to the fight, and was flagged by USADA as a potential anti-doping violation.

[59] On 19 July, the UFC announced that Lesnar tested positive for the same banned substance in a second, in-competition sample.

[60] On 23 August, the Nevada Athletic Commission confirmed that Lesnar twice tested positive for the estrogen blocker clomiphene, and that he has been temporarily suspended.

[68] However, on 10 October, Hunt was pulled from the card and was replaced by Fabrício Werdum after UFC officials reviewed Hunt's article, entitled, "If I Die Fighting, That's Fine"[69][70] on his health status from the consequences he suffered from his long term fighting career[71] (slur speech and loss of memory- an early signs of chronic traumatic encephalopathy (CTE)).

[72] Hunt was upset with the news, responding on his Instagram that the quote was taken out of context and that he had been cleared to fight by doctors two days before he was pulled from the bout.

… These guys don't get paid jack shit.On 5 December 2017, it was announced that Hunt had been cleared to fight[75] after undergoing medical tests in Las Vegas that were arranged by the UFC.

[84] Hunt faced Paul Gallen in a six-round heavyweight match on 16 December 2020 at Bankwest Stadium in Sydney, Australia.

[87] Hunt faced Sonny Bill Williams on 5 November 2022 at Ken Rosewall Arena in Sydney, Australia.

After Kintaman gained control of him, Hunt knocked out both C and Achichi and allowed the Hustle Army to win the match.

Hunt also holds a notable KO victory over Roy Nelson, who is cited as having one of the most durable chins in combat sports.

[107] Auckland's UFC team and Game of Thrones star Jason Momoa (Khal Drogo) performed "Haka – a traditional war cry, dance or challenge from the Māori people from New Zealand" to cheer and support Hunt for his fight against Derrick Lewis.