Wladimir is about 30lb heavier and four inches taller than Haye
David Haye has labelled Wladimir Klitschko a "B-level champion" ahead of their world heavyweight title fight in Germany on 20 June.
Londoner Haye also predicted that Klitschko would become a forgotten man after he "knocked him out".
"He's spent so many years fighting B-level opponents, he's become a B-level champion," said Haye.
"In 20 years' time no-one is going to remember him. He's just going to be the big dude I knocked out in Germany."
Haye, who will challenge for Klitschko's IBF and WBO belts at Schalke 04's Veltins Arena, incensed the Ukrainian in London on Monday by wearing a T-shirt which depicted him holding the severed heads of Wladimir and his brother Vitali, the WBC heavyweight champion.
The Briton wore the same t-shirt as he resumed his verbal assault on the Ukrainian during a press conference in New York on Thursday to promote the fight for American broadcasters HBO.
In the press conference after the fight I will make you eat your words and your T-shirt as well
Former undisputed cruiserweight champion Haye, 28, pointed to Klitschko's six title defences as evidence to back up his claims.
"You become what you're used to dealing with and he's used to dealing with guys that are out of shape, over the hill and who literally just turn up," he said.
"It's good for his record but these guys have had no desire. They've not been willing to go through it to get the victory."
He also specifically highlighted his opponent's last two defeats, to Lamon Brewster in 2004 and Corrie Sanders a year earlier, to show what a positive approach can achieve.
"Brewster took some punches and then knocked him out. Corrie Sanders took a few and wasn't scared and knocked him out.
"Since then he's been very, very clever and astute on who his opponents are, to make sure they don't expose the same things those guys showed."
Speaking later during the press conference, 32-year-old Klitschko repeated his promise to make Haye regret his words.
"In the press conference after the fight I will make you eat your words and your T-shirt as well," he said.
"It's not funny, you think you're a great promoter? I'll make you a great loser.
"You tried to get under my skin, you got under my skin. You've given me the perfect motivation for my training and for the fight. Whatever it takes to make you lose I will do it. I promise."