Early career Breese compiled an amateur record of 3–0–1 before successfully making his professional debut for
BAMMA in 2010. Breese fought exclusively in his native England and amassed an undefeated record of 7–0 with all but one win coming by way of submission before joining the
Ultimate Fighting Championship in 2015.
Ultimate Fighting Championship Breese made his promotional debut against Luiz Dutra Jr. on 30 May 2015 at
UFC Fight Night 67. Breese won the fight via TKO in the first round after dropping his opponent with a straight left and following up with ground and pound. Breese faced
Cathal Pendred on 24 October 2015 at
UFC Fight Night 76. Breese dominated the fight with striking exchanges en route to another TKO victory in the first round. In similar fashion to his UFC debut, Breese dropped his opponent with a straight left and followed up with ground and pound to earn the TKO victory. The win also earned him his first
Performance of the Night bonus award. Breese faced
Keita Nakamura on 27 February 2016 at
UFC Fight Night 84. He won the fight via unanimous decision. Breese faced
Sean Strickland on 4 June 2016 at
UFC 199. He lost the fight via split decision, marking the first loss in Breese's career. Breese was expected to face
Oluwale Bamgbose on 18 March 2017 at
UFC Fight Night 107. However, on the day of the event, Breese was deemed unfit to compete and the bout was cancelled. Breese faced
Dan Kelly on 27 May 2018 at
UFC Fight Night 130. He won the fight via technical knockout in round one. This win earned him the
Performance of the Night award. Breese was expected to face
Cezar Ferreira on 17 November 2018 at
UFC Fight Night 140. However, it was reported on 9 November 2018 that Breese pulled out of the event due to injury and was replaced by
Ian Heinisch. Breese was expected to face
Alessio Di Chirico on 16 March 2019 at
UFC Fight Night 147. However, Di Chirico pulled out of the fight in early January citing an undisclosed injury and subsequent surgery. He was replaced by
Cezar Ferreira. However, on 1 February 2019 Ferreira withdrew from the fight, citing a knee injury, and was replaced by
Ian Heinisch. In turn, Breese withdrew from the fight against Heinisch due to health concerns. Breese faced
Brendan Allen on 29 February 2020 at
UFC Fight Night 169. He lost the fight via TKO in the first round. Breese was scheduled to meet
Roman Kopylov on 4 October 2020. at
UFC on ESPN: Holm vs. Aldana. However, Kopylov was removed from the bout for undisclosed reason and he was replaced by KB Bhullar. The fight took place a week later at
UFC Fight Night: Moraes vs. Sandhagen. Breese won the fight via technical knockout in round one. This win earned him the
Performance of the Night award. Breese was expected to face
Omari Akhmedov on 16 January 2021 at
UFC on ABC 1. During fight week, the UFC opted to move the bout to
UFC on ESPN: Chiesa vs. Magny. He lost the bout via second round arm triangle submission. Breese was scheduled to face
Antônio Arroyo on 5 June 2021 at
UFC Fight Night: Rozenstruik vs. Sakai. However, the fight would be cancelled a few hours before it was to take place due to medical issues suffered by Breese.
Levels Fight League After the pull out from his last bout, Breese was released from the UFC and signed a multi-fight deal with Levels Fight League. Breese made his debut against David Ramirez at LFL 4 on 13 March 2022. He won the fight by submission due to rear naked choke at 1:46 of the second round, winning the LFL Middleweight title in the process. Breese defended his title against Ahmed Sami at Levels Fight League 5 on 26 June 2022. He won the bout and kept the title, submitting Sami in the second round via guillotine choke.
Konfrontacja Sztuk Walki Breese made his
KSW debut against
Damian Janikowski on 10 September 2022, at
KSW 74, controversially winning via guillotine choke in the second round, with the bout being stopped after the ref thought that Janikowski tapped when he said he didn't. In his sophomore performance, Breese faced
Paweł Pawlak on 12 November 2022, at
KSW 76: Parnasse vs. Rajewski, losing the bout via ground and pound TKO in the first round. Breese faced Bartosz Leśko on 17 March 2023, at
KSW 80: Ruchała vs. Eskiev, submitting him via rear-naked choke in the first round.
Return to LFL and double championship After the stint in KSW, Breese returned to the Levels Fight League, challenging the reigning LFL Light Heavyweight champion Jarosław Lech at LFL 9 on 9 July 2023. Breese became an LFL double champion by submitting Lech in the first round. On 10 October 2023 KSW announced that Breese was no longer under contract with the promotion.
Professional Fighters League After leaving KSW, Breese signed with the
PFL and made his debut against Cleiton Silva on 8 December 2023 at
PFL Europe 4. He won the fight via a rear-naked choke submission in the first round. Breese started the 2024 season with a bout against
Rob Wilkinson on 12 April 2024 at
PFL 2. He lost the fight by first-round technical knockout with a knee and punches. Breese was scheduled to face
Sadibou Sy on 21 June 2024 at
PFL 5, however he pulled out for unknown reasons. ==Championships and achievements==