Bellew, 35, is currently preparing to face Haye for the second time in just over a year after he caused an upset by defeating the former heavyweight world champion -- who was hampered by an Achilles injury -- by 11th-round knockout in March 2017.

The return bout was originally scheduled to take place on Dec. 17 but was postponed after Haye tore his left bicep and was forced to undergo surgery to fix the issue.

The fight at London's O2 Arena comes 13 years after the Liverpudlian was brought into the Haye camp to help the former cruiserweight prepare for his 2005 grudge-match with Mark Hobson -- a fight that never happened due to the Bermondsey fighter sustaining a hamstring injury which Bellew takes credit for.

"He didn't even know who I was at the time, I had just won my first ABA title," recalled Bellew, who was joined in the sparring sessions by close friend David Price. "He came up to Liverpool and he got punched all over the place.

"Me and David Price turned him over that day, we punched him everywhere and the next day he pulled out of the fight against Hobson with an injury. That's a fact.

"We were told if we could drop him, we would get a £1,000 bonus payment. At the time, I was skint. They paid us £100 to spar," added Bellew, who is expected to pocket a significantly larger sum from the pair's upcoming meeting. "I couldn't believe that anyway, then the bonus on top."

Despite coming away from their last fight as the winner, Bellew continues to be seen as the underdog in the eyes of many and admits that he has never been hit harder than he was during his first meeting with the Hayemaker over a decade ago.

"In the first round of that sparring, his first punch -- I've never been hit as hard in my life, and I've been stopped before," conceded Bellew.

"He hit me with a right uppercut. I was just standing here, looking at him and my leg just kicked out at me for no reason -- like a donkey.

"I said to him 'good shot' and the look on his face that I was still standing was a picture. He was gutted."

Although Bellew admits that he did not manage to win the bonus, he recalled that Price came close to flooring Haye.

"He was doing four minute rounds," Bellew continued. "Two minutes with Pricey and then two minutes with me.

"Price hit him on the chin and I kid you not, he spun around 360 degrees, his whole body.

"Pricey is the nicest person ever, so when Haye is spinning round, Pricey stood there and watched him. I went 'f-----g kill him! Jump on him!' But he didn't even though we were getting a bonus."