Anthony Joshua claims Deontay Wilder and Tyson Fury have blown their best chance of beating him.
Joshua says heavyweight rivals Wilder and Fury are playing into his hands by refusing to fight and neither of them will face him until next spring at the earliest.
Joshua feels the delay benefits him because at 29 and with just over five years as a pro, he is still improving, while the older Wilder and Fury are at their peaks now.
Joshua, who defends his WBA Super, IBF and WBO titles on his US debut against Andy Ruiz Junior at Madison Square Garden on Saturday, said: “I don’t know what they’re waiting for.
"They’re coming to the end of their careers, 10, 11 years as professionals. I’ve been doing it five years.
“The longer they leave it, I don’t think they’re going to get much better. It’s worse for them because I have another five years honing my skills.
“I’m not the finished article yet. I’m still working towards certain things so imagine another five years or another 18 months for my bag of tricks. I’ll have a few more skills.
“The longer they leave it, the worse it’ll be for them so they should crack on.”
Joshua, who arrived in New York yesterday, questioned Wilder’s ambition and said he can’t understand why the WBC king does not challenge him to become the undisputed world heavyweight champion.
Wilder, 33, rejected a three-fight deal from Joshua’s broadcaster DAZN worth around £75million, which would have seen them clash twice, to leave the Briton baffled.
The American has stuck with US broadcaster Showtime and Joshua said: “If in five or 10 years from now I had the opportunity to become undisputed champion, where else would I go?
“I’d have done it for 10 years, I’d have done my defences, I’d have done my learning. Then it would be time to stamp my name on history. I’d be chomping for that.
“I want it after 20-odd fights. He’s had 40-odd fights and five more years, so I don’t know where he’s going.
“He turned down double the amount to fight me and that was a real offer from a broadcaster. That wasn’t an email from Wilder, it was a real contract offer from a broadcaster offering Wilder the chance to fight on DAZN.
"A contract offering him a chance to fight one warm-up then me. And he could have fought me straightaway if he’d wanted, there was that option. It’s baffling to know why he didn’t take it after all the talk.
“How much more money has to be on the table? Broadcasters run boxing. But then we’ve had this situation before when fighters were on different broadcasters and still managed to fight.
“There is the promotional side too and promoters protect their fighters, which is right. But if you believe in your fighter and they become undisputed, then you’re in a win-win situation. You take the risk and get the reward.”
