Gwynne made his professional debut on 23 July 2016, scoring a four-round points decision (PTS) victory against Joe Beeden at the Rhydycar Leisure Centre in Merthyr Tydfil, Wales.
In a fight which served as a final eliminator for the British lightweight title,[6] Gwynne defeated Mills via ten-round unanimous decision (UD) with the judges' scorecards reading 97–93, 96–94, and 96–94.
[7] Following an eight-round PTS victory against Arnoldo Solano in June 2019,[8] Gwynne challenged British and Commonwealth lightweight champion Joe Cordina on 31 August at The O2 Arena in London.
In a fight which saw both men receive a point deduction for committing fouls, Gwynne suffered the first defeat of his professional career, losing by UD with the judges' scorecards reading 116–110, 116–111, and 116–111.
In a fight which saw Gwynne suffer a cut to the back of his head as a result of an accidental elbow strike, he dropped his opponent to the canvas in the sixth round en route to a seventh-round TKO victory after McComb turned his back on Gwynne, prompting the referee to step in and call a halt to the contest.