Eddie Hearn believes Anthony Joshua will be the best heavyweight boxer in the world for the next decade as the Brit prepares to step into the ring with Dominic Breazeale on Saturday.
Joshua took the IBF belt off Charles Martin with a second-round stoppage in April and will make the first defence of his title against American Breazeale at the O2 Arena in London this weekend.
Olympic super-heavyweight champion Joshua has won all 16 professional fights by knockout and his promoter Hearn is in no doubt that the 26-year-old will dominate his division for years to come.
"I think I've got the best heavyweight for the next 10 years on the planet. I can't see anyone beating him. I think the kid is outstanding and I think he's got a lot of improvement left in him yet," he told Sky Sports.
"Even as he is today, he's the best heavyweight in the world. What he's going to be like in two years' time is frightening."
Hearn's claim comes despite the fact that Joshua's compatriot Tyson Fury holds the WBA and WBO belts after a stunning defeat of Wladimir Klitschko last November.
Fury and Klitschko will contest a rematch in Manchester on July 9 and Hearn is hoping the Englishman comes out on top, but stated that a fight with Joshua will still be on offer if he is dethroned.
Hearn added: "Tyson had an amazing result to beat Klitschko, but you have to say that Klitschko only threw five punches in the entire fight. If the real Klitschko turns up, Tyson could have a problem.
"If Klitschko is completely shot, Fury will win again, and I really hope that he does. If Klitschko turns up, he could make Tyson look silly. We have to wait and see, but win or lose there is a massive fight with Anthony Joshua. Win or lose.
"I would rather he won, because it's even bigger. It's an 80,000 sell out at Wembley, it's a million pay-per-view buys, plus the global, because it's a great fight to watch.
"I know the Joshua camp really want that fight. It's a very straightforward fight for Joshua, very straightforward. But it doesn't really matter - my thoughts are only my opinion.
"When they get in the ring, then we'll see what they've got. I think Fury is made for Joshua, because of the way he boxes, the way he stands.
"He's not a great big puncher and he can't take a shot. That's my view. I mean [Steve] Cunningham dropped him. When a cruiserweight puts you on your ass, you have to ask some serious questions.
"But he's very engaging, he'll sell the fight, and it will be a massive, massive fight."