TMZ Sports talked to Eddie Hearn -- Joshua's promoter -- after he announced AJ's fighting undefeated heavyweight star Jarrell "Big Baby" Miller June 1 at MSG in NYC ... his first fight in America.
Hearn says Big Baby is a big, tough dude who could actually beat Joshua ... but, if the British superstar does survive, he's got his sights set on Wilder and Fury.
"We 100% want the winner. Joshua wants to be the undisputed champion. He has 4 world heavyweight belts. He's missing 1. And, that's the missing link. And, that's everything that he wants."
Deontay and Tyson's rematch isn't a done deal just yet -- but, it's reportedly close -- and would likely go down in April or May.
"Those two will fight, I think. And then hopefully Joshua deals with Jarrell Miller, and then it happens later this year."
"You're gonna get all these fights. This isn't about June 1. This is about a legacy. This is about another 5, 6 years of him trying to dominate the division, and I personally believe he will go through everybody."