Daniel Dubois‘s punching power has been well- documented since he emerged onto the heavyweight scene aged just 19.

He turned professional back in 2017 and went on a run of knockout wins, stopping his first eight opponents before US veteran Kevin Johnson was the first man to survive and lose on points.

More knockouts followed against the likes of Nathan Gorman and Richard Lartey, but it was fellow Brit Joe Joyce who halted Dubois with a relentless jab fractured his eye socket back in 2020.

Dubois has rebuilt since then with wins over Trevor Bryan, Kevin Lerena and two impressive stoppages of Jarrell Miller and Filip Hrgovic last time out, though did lose to Oleksandr Usyk in 2023 on the Ukrainian’s way to becoming undisputed.

Next up he has another stern test when he faces Anthony Joshua on September 21 to defend his newly-received IBF world title.

Ahead of that bout, speaking to Title Sports Network, Big John Fisher, the father of heavyweight contender Johnny Fisher, spoke about sparring sessions between the two.

“Johnny has sparred Dubois spare countless rounds and I’ve seen many of them and he’s come out of those spars, held his own, done well, but when he’s got home he’s been a broken man cause Daniel hits hard. He tries to take your head off in every sparring session.”

Despite that he predicted a tough night for Dubois.

“He’s a good bloke, I’ve got a lot of time for him, lot of respect for him, but also for AJ, he’s a top man, hit a bit of form lately, and I think if AJ connects like what Hrgovic did, it’s gunna be a tough night for Daniel, but he always has a chance with his power. It’s a great fight, great match up “

Dubois’s former opponent Miller is one of the few men to claim that Dubois in fact doesn’t hit hard.

Fisher continues to build on his undefeated record, most recently with a first round blowout of Alen Babic in London.