Dubois’ boxing prowess has been clear from a young age.
As part of the England amateur set-up, he was sparring with the likes of Joshua, Joe Joyce and Frazer Clarke.
“I couldn’t believe it,” Clarke said. “His punch power for a kid who was about 17 was phenomenal.”
A scintillating start to his pro career yielded 14 stoppages in 15 fights. Dubois was heralded as the future of the division.
But he soon experienced the fickleness of pro pugilism in a significant step-up.
Dubois suffered a broken eye socket during his loss to Joe Joyce in 2020, having taken a knee and missed the count.
“People called him a coward and quitter, and that just wasn’t true,” Warren said.
Dubois faced the same criticism when he was stopped by Oleksandr Usyk in his first world title challenge last year.
But Dubois is not overly active on social media and was to some extent shielded from the negativity, and the shift from praise to condemnation also means the burden and pressure of being Britain’s next heavyweight hope had eased.
Warren asked Dubois to “grit his teeth” in tough battles and he seems to have listened.
He did not buckle under pressure from Miller and shrugged off huge right hands from Hrgovic, winning both crucial fights inside the distance.