Clarke turned professional in January 2022, signing a promotional deal with Eddie Hearn's Matchroom Boxing[8] and made his pro-debut on 27 February that year knocking out Croatia's Toni Visic in round two at The O2 Arena in London, England.

[9] On 27 January 2024, he won his first professional title, claiming the vacant WBA cruiserweight Intercontinental belt with a fourth-round stoppage of Tommy McCarthy at Ulster Hall, Belfast, Northern Ireland.

[11] Defending his WBA Intercontinental title, Clarke defeated Efetobor Apochi by majority decision at Dignity Health Sports Park, Carson, California, on 31 August 2024, with two ringside judges scoring the fight in his favour 98-92 and 97-93 respectively while the third had it a 95-95 draw.

[12][13] Clarke fought unbeaten French boxer Leonardo Mosquea for the vacant European cruiserweight title in Monte Carlo on 14 December 2024, suffering his first loss as a professional by split decision with one judge scoring in his favour 117-113 but being overruled by the other two who had the bout 116-112 and 115-112 respectively for his opponent.

[14][15] Clarke is set to face English Cruiserweight champion Viddal Riley on the undercard of Chris Eubank Jr vs Conor Benn on 26 April at the Tottenham Hotspur Stadium.