Hardy believes Ngannou – who signed a multi-fight deal with mixed martial arts league PFL in May – did the “unthinkable” and said he had him winning the fight on his own scorecard.
PFL Europe Head of Fighter Operations Hardy told the PA news agency: “For Francis to hold his composure like he did and to outpoint and outbox him was unthinkable.
“It is the biggest upset in boxing history even though he didn’t get the decision.
“I had him winning the fight. I have my scorecard and I had him 96-93 because of the knockdown in the third and I stand by it. Ngannou certainly won the fight.
“It was an unfair decision, Francis deserved the victory and deserved the nod. But it was a close fight, no doubt about it.
“I was blown away and I still am. I think right now Ngannou is the king of combat sports, he is the biggest combat sport athlete because of what he achieved on the weekend.”
Fury had written off Ngannou’s chances in the build-up, comparing the fight to “a table tennis champion facing (Novak) Djokovic in the Wimbledon final”.
Hardy added: “I think (Fury overlooking Ngannou) was a big part of it.
“It was a perfect storm on the night and that to me looked like Tyson Fury halfway through training camp expecting a sparring match ahead of the Oleksandr Usyk fight.
“I don’t think he looked at Ngannou with the same fear he would Deontay Wilder.
“After the third round Fury would’ve been thinking ‘I wish I prepared better for this, I wish I came in lighter’.”
Hardy believes former UFC champion Ngannou has a future in heavyweight boxing and that he can go toe-to-toe with the division’s best.
He said: “I think we’ll see him fight in Professional Fighters League and then see him move back into the boxing world and have another big fight.
“Who else in the top 10 can he give problems to? And the general consensus now is quite a few of them. The two that come to my head are Joe Joyce and Anthony Joshua.
“The Francis we saw against Tyson at the weekend would cause those two serious problems stylistically.
“I think he can have a career in boxing if he wants to and he’s going to be ranked soon so the door’s open for him.
“Wilder is an obvious opponent, because it would be two of the biggest punchers on the planet.
“Wilder does not have the same finesse as Fury.”
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