David Haye believes former foe Tony Bellew could "cause an upset" and beat undisputed cruiserweight world champion Oleksandr Usyk.
Bellew will challenge the unbeaten Ukrainian for his IBF, WBA, WBC and WBO titles at the Manchester Arena, on November 10, live on Sky Sports Box Office.
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'Bomber' will be the underdog and he steps back down to 200lbs following two heavyweight wins over Haye, who has not ruled out another major surprise.
I definitely feel you underestimate Tony Bellew at your peril.
"Any guy over 13st has a chance of beating anyone," Haye exclusively told Sky Sports.
"Whoever says 'he's got no chance against Usyk' were the same people who said 'he's got no chance against David Haye, he's too big and too strong'.
"I definitely feel you underestimate Tony Bellew at your peril."
Haye himself was a unified cruiserweight world champion 10 years ago, when sensational wins over Jean-Marc Mormeck (WBC) and Enzo Maccarinelli (WBO) saw him claim three of the four titles Usyk is now putting on the line.
Bellew was crowned WBC champion when he became the first fighter to beat Ilunga Makabu two years ago and 'Hayemaker' thinks the underdog tag will suit the Liverpudlian perfectly again.
"A lot of people didn't give Tony Bellew a chance of beating me on both occasions, and he did," said Haye.
"That's the thing, no one gave Tony Bellew a chance of winning the cruiserweight title as well, and he did it.
"If anyone's going to be able to cause an upset from being an underdog, the guy who has consistently been that guy is the guy to do it again."
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