David Haye has predicted that his fighter Derek Chisora will be able to pull off an upset similar to when Teofimo Lopez beat Vasiliy Lomachenko when he faces Oleksandr Usyk on Saturday.
Usyk (17-0, 13 KOs), 33, is a betting favourite to preserve his status as WBO mandatory challenger against Chisora at the Wembley Arena in London (32-9, 23 KOs), 36, in a show without fans due to coronavirus restrictions.
Chisora will be Usyk's second opponent at heavyweight after stepping up from cruiserweight last year following a reign as undisputed world champion.
Usyk is attempting to follow the likes of Haye and Evander Holyfield in winning world titles at both cruiserweight and heavyweight.
But Haye, who retired in 2018 and now manages Chisora, believes size will be an issue for Usyk just as it was when his fellow Ukrainian Lomachenko lost to American Lopez on points in a big shock to become undisputed world lightweight champion earlier this month.
"You saw what happened when Lopez fought Lomachenko the other week, when size negated a skill set, and this will be the same," Haye told ESPN.
"Usyk did everything at cruiserweight, he was a unified champion and beat all the other champions. He has shown what he can do at cruiserweight but that's against guys who are 200 pounds.
"A fully firing Derek Chisora that we saw against David Price, Artur Szpilka, has punching power at heavyweight. Usyk on the other hand didn't look like a guy that wanted to make a statement at heavyweight against Chazz Witherspoon.
"He will want to up his game this time around and stake his claim to challenge for the WBO title, he will want to make noises, but can he deal with the power and size and work rate? I don't think he can do it. Derek will grind him down and knock him out. I think Derek will provide a seismic upset."
Haye might manage Chisora, but in 2012 they were bitter enemies which was settled by a knockout win by Haye.
Haye reckons Chisora's strength will be the decisive factor and is urging his fellow Englishman to keep the fight at close range when he faces Usyk, who stopped Tony Bellew in eight rounds in his last visit to the UK in November 2018.
"The fight when I felt the difference between cruiserweight and heavyweight the most was actually against Derek Chisora," Haye said.
"He used his size more than someone like Wladimir Klitschko, who boxed cleanly at long range. Derek wanted to get in close so I had to do a lot of wrestling training to get used to it. If Usyk is not doing that in training he will really start feeling the pace in the later rounds.
"Derek will not be boxing long and throwing out long jabs because he's not that sort of technical boxer but when it comes down to blood and guts and who can drown the longest, then it is Derek. He has to do the close-range fight.
"Usyk isn't as resilient as Derek, he's more technical and has lighter feet for sure, but in the clinches and gritting it out I'm going for Derek Chisora all day long."
Victory for Chisora, who was knocked out by Dillian Whyte two years ago, could see him challenge English rivals Anthony Joshua, the WBA-IBF-WBO world champion, or Tyson Fury, the WBC champion, next year.
"If Derek Chisora does a job on Usyk he's right there knocking on the door or a world title shot with Joshua or Fury," Haye said. "If he beats Usyk, he takes his mandatory position with the WBO, and Usyk is also No. 2 with the WBC and WBA. Fighting either Joshua or Fury is a very marketable fight for the UK. It's as important as a world title fight for Chisora and Usyk."
Haye added that Chisora's preparations this year for Usyk have left him in perfect shape, despite the disruption and complications caused by coronavirus restrictions.
"In preparations over the last two years we have never had a run that has gone smoothly," he said.
"But this time he hasn't got sick or got any injuries. All of the work with the coaching staff, strength and conditioning staff, have come together and the results are speaking for themselves in terms of rounds sparred and punch output.
"Everything is where we hoped it would be. We had an ideal training programme and nine times out of ten you have to adapt to it because of circumstances. But for this camp we have completed all the aims, I'm very confident we are going to see Derek Chisora at his optimum best."