Aged 17, Diakiese began training in mixed martial arts to keep fit and stay out of trouble.

[5] After four wins in under a year in regional promotions, Diakiese joined BAMMA on a five-fight contract in 2014.

[6] In September, he made his promotional debut against Jefferson George at BAMMA 16 and won the fight by unanimous decision.

[8] In March 2015, Diakiese faced Jack McGann at BAMMA 19 for the vacant Lightweight Championship.

[9] In September, he defended his title at BAMMA 22 with a knockout 24 seconds into the first round against Rick Selvarajah.

Diakiese finished Kane Mousah in 36 seconds at BAMMA 25 and subsequently earned a UFC contract.

[15] Diakiese returned to face Frankie Perez on 9 December 2016 at UFC Fight Night: Lewis vs.

[31] Diakiese was scheduled to face Stevie Ray on 21 March 2020 at UFC Fight Night: Woodley vs.

[39] However, Alves pulled out of the fight in mid-August for undisclosed reasons and in turn, Diakiese was removed from the card as well.

[43] He won the fight by unanimous decision after controlling Borshchev on the ground for nearly twelve and a half minutes.

[44] As the first bout of his new four-fight contract, Diakiese faced Damir Hadžović on 23 July 2022 at UFC Fight Night 208.

[53] It was reported on 8 June 2024 that Diakiese signed with the Professional Fighters League (PFL) and will compete this year.

[54] In his debut for the promotion, Diakiese faced Tim Wilde on 14 September 2024 at Bellator Champions Series 5.