Oleksandr Usyk's team admitted that Derek Chisora could have received a sensational win over the pound-for-pound star, says the British contender's manager David Haye.
Chisora troubled Usyk with his constant aggression last October, but the Ukrainian triumphed by unanimous decision with two narrow scores of 115-113 and a third wider margin of 117-112.
Haye has claimed that Usyk's management were even contemplating defeat and believes Chisora has been instilled with fresh belief ahead of Saturday's fight against Joseph Parker, live on Sky Sports Box Office.
"We've had many, many moments over the years," Haye told Sky Sports. "The high point for me, was the final bell against Oleksandr Usyk, in his last fight.
"He really pushed it and I was sitting with Usyk's team and they all looked at me and said: 'Derek has won that fight.'
"They were scoring it, they had Derek winning by one or two rounds, and they said it was a close fight, but we definitely feel Derek won that fight.
"I thought he won the fight as well, although the judges had it the other way."
Usyk, who joined the top division after becoming undisputed champion at cruiserweight, is the mandatory challenger for Anthony Joshua's WBO title.
But the supremely skilled southpaw rated his performance as three out of 10 against Chisora, admitting he was drawn into a dogfight.
Haye said: "Derek Chisora, who has lost 10 professional fights now, was able to push the No 1 contender in the world at heavyweight to the absolute limit and lose on such a fine margin.
"That showed to me that okay, everyone thought he was going to get his head boxed off, that he was going to get absolutely annihilated, and he didn't.
"It was because he did what he needed to do in those training sessions to give himself the best chance. Although it was a lowlight, it was still a highlight to know that it can be done.
"He was very close. Hopefully what we missed out on last time, we'll be able to go that little bit further."