The two Brits will go head-to-head at Wembley in September as Dubois defends his IBF heavyweight title against Joshua.
It's already a highly-charged encounter, with the pair having to be separated during the press conference to announce the fight, but Hearn says that although Dubois is a big hitter, Joshua will outgun the champion.
“Both are going to be letting their hands go,” he told BoxingScene.
“Both are very dangerous. Some people call it a ‘shootout’. But I think AJ’s top sniper. He’s too accurate; he’s too good; and I think if you’re going to get hit against Anthony Joshua you’re going to have serious problems, and AJ’s not gonna stand in front of him like Filip Hrgovic and just ship shots.
“It’s two very dangerous heavyweight punchers, who are in the form and confidence of their career. For Dubois, the Miller and the Hrgovic fight have taken him to the most dangerous point of his career so far. It’s not a good time to fight Dubois, and it’s definitely not a good time to fight AJ. The key points for me are two massive punchers in their absolute primes.”
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