Anthony Joshua’s comeback fight will take place on 1 April at the O2 Arena in London, against Jermaine Franklin.
Joshua and Franklin will go head-to-head at a press conference next week after reaching an agreement for their fight.
A news conference will be held next week to officially announce the fight.
Joshua, 33, is likely to fight American Jermaine Franklin, who lost on points to Dillian Whyte last November.
“It’s a really tough fight with loads of pressure to come back because if AJ doesn’t win this fight, then we’ve got a major problem,” said Hearn.
“I believe you’ll see a statement from a guy who is very dangerous, very motivated to become a three-time heavyweight world champion.”
Joshua has lost his last two fights, both to unified heavyweight world champion Oleksandr Usyk.
The Watford fighter is a two-time heavyweight world champion and has 24 wins, as well as three defeats.
Matchroom promoter Hearn dismissed the suggestion that 29-year-old Franklin was an easy opponent for Joshua.
Franklin was unbeaten before losing to Whyte. He was unhappy with the scoring of that fight, feeling he won the contest.
“There’s so much contradiction: ‘Anthony Joshua is finished, mentally he’s shot, but he’ll knock out Jermaine Franklin inside three rounds,'” Hearn told 5 Live Boxing in New York.
“The same people that say Jermaine Franklin beat Dillian Whyte but he’s a terrible opponent for Anthony Joshua, in a comeback fight after two defeats to the pound-for-pound number one.
“What this guy has done from a resume perspective is unbelievable.
“And I’m telling you now, this guy – still top-three heavyweight, capable of regaining his heavyweight world title.”
