Early career After going 9–1 as an amateur, Herbert made his professional MMA debut in 2015. He recorded consecutive second-round knockouts with Full Contact Contender and later signed a four-fight contract with
BAMMA. On 14 November 2015, Herbert made his promotional debut at BAMMA 23 and beat Ben Bennett via knockout in the second round. On 14 May 2016, he earned a second round submission against Tony Morgan at BAMMA 25. On 16 December, he suffered his first loss against future UFC fighter Rhys McKee in a lightweight title bout at BAMMA 27. In February 2017, Herbert was due to face Steve Owens at BAMMA 28, but his opponent was forced to withdraw with illness the day before. On 12 May, Herbert beat Rick Selvarajah at BAMMA 29 via knockout in the second round. In late 2017, Herbert voiced his displeasure about BAMMA's matchmaking. Due to an over-booking of fights by the promotion, Herbert saw a scheduled bout cancelled at late notice due to the number of tickets sold by the fighters. He announced he would not fight under the BAMMA promotion again and subsequently signed with
Cage Warriors. He was due to face
Marc Diakiese as a replacement at
UFC Fight Night: Woodley vs. Edwards in March, but the event was later cancelled due to the COVID-19 pandemic. On 25 July 2020 Herbert faced
Francisco Trinaldo at
UFC on ESPN 14. He lost the fight via knockout in round three. Herbert faced
Renato Moicano on 26 June 2021 at
UFC Fight Night 190. He lost the fight via a rear-naked choke in round two. Herbert faced
Khama Worthy on 23 October 2021 at
UFC Fight Night 196. He won the bout via TKO in round one. Herbert was scheduled to face
Mike Davis on 19 March 2022 at
UFC Fight Night 204. However, Davis withdrew from the bout for personal reasons and he was replaced by
Ilia Topuria. Herbert landed a head kick in the first round that dropped Topuria, but ultimately lost the fight via knockout in round two. Herbert faced
Kyle Nelson on 23 July 2022 at
UFC Fight Night 208. He won the fight by unanimous decision. Herbert faced
Ľudovít Klein on 18 March 2023 at
UFC 286. After a point deduction in the third round due to multiple groin strikes, the fight ended in a majority draw. Herbert faced
Farès Ziam on 22 July 2023 at
UFC Fight Night 224. He lost the fight via unanimous decision. Herbert faced Rolando Bedoya on 3 August 2024 at
UFC on ABC 7. He won the fight by unanimous decision. Herbert faced Chris Padilla on 22 March 22 2025, at
UFC Fight Night 255. He lost the fight by split decision. Herbert faced Mandel Nallo on 18 April 2026 at
UFC Fight Night 273. He won the fight by technical knockout in the first round. ==Championships and accomplishments==