Hunt faced Roy Nelson on 20 September 2014, at UFC Fight Night 52. He won the fight via knockout in the second round. The win earned Hunt his first Performance of the Night bonus award, and the World MMA Awards' 2014 Knockout of the Year award.

On 21 October 2014, it was announced that Hunt would replace injured UFC Heavyweight Champion Cain Velasquez in the main event of UFC 180. He faced off against Fabrício Werdum for the interim UFC Heavyweight Championship. Despite having early success and dropping Werdum twice, Hunt lost the fight via TKO in the second round.

Hunt faced Stipe Miocic on 10 May 2015, at UFC Fight Night 65. He lost the fight via TKO in the fifth round. Miocic set a UFC record for the most strikes landed in a fight, outlanding Hunt 361 – 48 over the duration of the bout.

Hunt faced Antônio Silva in a rematch on 15 November 2015, at UFC 193. Hunt won the fight via TKO, after dropping Silva with a straight right up against the fence at 3:41 of the first round.

Hunt faced Frank Mir on 20 March 2016, at UFC Fight Night 85. He won the fight via KO in the first round after sending Mir to the canvas with a right hand. He was awarded with Performance of the Night for his efforts. It was later announced that Mir failed an in-competition drug test.

Despite talks about Hunt's current contract being his last, on 14 April 2016, it was announced that Hunt had signed a new six-fight, multi-million dollar contract with the UFC.

Hunt faced a returning Brock Lesnar on 9 July 2016, at UFC 200. He lost the fight via unanimous decision. However, on 15 July, it was revealed that Lesnar had tested positive for a banned substance in a pre-fight drug test. 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. On 19 July, the UFC announced that Lesnar tested positive for the same banned substance in a second, in-competition sample. 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. Due to Lesnar's positive tests, the result of the fight was changed to a no contest.

Hunt faced Alistair Overeem in a rematch on 4 March 2017, at UFC 209. He lost the fight via knockout in the third round.

Hunt faced Derrick Lewis on 11 June 2017, in the main event at UFC Fight Night 110. It was the first combat sports event in Auckland since UFC Fight Night 43 in Vector Arena. He won the fight via TKO in round four. The win also earned Hunt his third Fight of the Night bonus award.

Hunt was expected to face Marcin Tybura on 19 November 2017, at UFC Fight Night: Hunt vs. Tybura. 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" on his health status from the consequences he suffered from his long term fighting career (slur speech and loss of memory- an early signs of chronic traumatic encephalopathy (CTE)). 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.
Extract the number of fights Hunt won by knockout or TKO in the below text and the year he had the most knockout wins
Mark Hunt won four fights via knockout/TKO with two of these wins coming in 2015