Joshua will look to become the first man to defeat Usyk in the professional ranks as the former undisputed cruiserweight champion looks to topple the Brit in front of a home crowd.
But Hearn, who has promoted Joshua since his pro debut in 2013, does not believe the Ukrainian possesses the kind of scary power that some other heavyweights carry.
Speaking to BBC Sport, he said: “I think everyone can punch. I don’t think he is a puncher.
“That doesn’t mean you can’t be fearful of him as a puncher because he is sharp and sometimes he hits you from angles with shots that you don’t see and sometimes they’re the deadliest ones.
“I’m sure he can hurt all heavyweights, but I don’t fear his power in this fight like I would watching AJ against Wladimir (Klitschko) or against (Deontay) Wilder if that fight happened.”
Usyk, an Olympic gold medallist, has stopped 13 of his 18 opponents since turning pro in 2013 - the same year as Joshua.
The 34-year-old has knocked out a number of high-profile names including Marco Huck and Tony Bellew.
However, he did go the full 12 rounds with Dereck Chisora last time out, while Joshua stopped Kubrat Pulev inside the distance.
Joshua is the bookies favourite heading into the fight this weekend, but Usyk remains arguably the Brit’s toughest challenge to date.
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