Anthony Joshua will fight one of Oleksandr Usyk, Kubrat Pulev or Dillian Whyte later this year, assuming he beats Andy Ruiz Jr on Saturday night.
Joshua defends his three heavyweight world titles against the Mexican American at Madison Square Garden.
He had hoped victory would propel him into a unification clash against Deontay Wilder but his fellow champion will instead fight Luis Ortiz.
That leaves Joshua looking for an opponent for an autumn date, potentially at the Millennium Stadium, with the aforementioned trio the frontrunners.
When asked about if a fight against Tyson Fury was a possibility, Hearn told iFL TV: "A little bit yeah, we have to take care of our mandatories as well.
"WBO mandatory, IBF mandatory. The WBO haven’t ruled yet, but we have a WBO mandatory due, it could be [Usyk].
"We have an IBF mandatory due in Pulev. We’ve got maybe even a Dillian Whyte fight we just jump into in November.
"If Joshua’s not on his game, he won’t beat Ruiz and then we’re rematching Ruiz!"
Hearn also accused Wilder of announcing his rematch with Ortiz hours after Joshua had called for face-to-face talks with the American.
"Joshua goes on ESPN and says, 'I'll sit down with you after my fight and we’ll do a deal'," he added.
"And he goes, 'S***. How can we look okay out of this? Oh yeah, I've signed a deal to fight Ortiz everybody.'
"What, that morning? It’s embarrassing, that’s what it is…
"Stop talking about Wilder, he's a waste of time. They don’t want the fight, he's been talked into doing something else.
"He's not his own boss, he don’t make his own decisions, let him do what he’s been talked into.
"When he becomes available, after he’s fought Ortiz, after he’s fought [Adam] Kownacki, then I guess we’ll try again."
