[4] In 2019, he was selected to compete at the World Championships in Yekaterinburg, Russia,[5] where he won the bronze medal after losing by unanimous decision to Dilshodbek Ruzmetov in the semi-finals.

English media personality Piers Morgan tweeted: "Love this - finally, an athlete at these Olympics prepared to tell the truth about competing in elite sport.

[10] On 31 March 2024, Whittaker fought at The O2 Arena in London, England on the undercard of a British heavyweight title fight between Fabio Wardley and Frazer Clarke.

On 12 October 2024, Whittaker made his first defence of his IBF International light-heavyweight title against Liam Cameron on the undercard of Artur Beterbiev vs. Dmitry Bivol.

A witness alleged that Whittaker had said: "'Don't take no photos of me' and snatched the phone out of [the fan's] hand and smashed it straight on the floor.