Haye (right) is giving away a massive weight and height advantage
Evander Holyfield has questioned David Haye's heavyweight credentials ahead of the Londoner's bout against WBA champion Nikolay Valuev in November.
Like Haye, Holyfield was an undisputed cruiserweight champion before moving up to claim the heavyweight crown.
Unlike Haye, who has had just one tune-up bout at heavyweight, Holyfield had six before fighting for a world title.
"We're different, I didn't have one fight and then get my opportunity," Holyfield told BBC Sport.
"I moved up in 1988 and had six fights in two years before I was finally ranked number one and got the opportunity to fight the winner of Mike Tyson-Buster Douglas.
"When people try to compare David Haye to me, I say, 'wait a minute, I fought six heavyweights and beat them, they didn't make me number one contender straightaway'.
"I fought my way in to prove I could win the heavyweight title. I fought more as a heavyweight than I did in any other division.
"David Haye only fought one fight, and it will only tell you how good he is by how well he does in the fight against Valuev.
"He's a very skilful fighter, but he's moving up to the heavyweight division and he's fighting against a giant, a guy who's 100lb heavier and has a huge reach advantage."
The 47-year-old Holyfield, the only man to win a heavyweight title four times, fought Valuev last December, losing on points when many observers felt he should have been awarded the decision.
Haye has fought as a heavyweight on three occasions, but only once since relinquishing his cruiserweight belts, against American Monte Barrett last November.
Haye, 28, knocked Barrett out in the fifth round, but did not have it all his own way, finding himself on the canvas at the start of round five.
He will come up against the 7ft 2in Russian at the Nuremberg Arena on 7 November, and Holyfield has not ruled out fighting him should he emerge victorious.
Holyfield fought well against Valuev but lost by a majority points decision
"I'll be fighting in November and hopefully in February or March I'll be fighting for a world title," said Holyfield.
"It's not a dream, it's a reality, it just hasn't happened yet. If I become world champion I won't fight him [Haye], but if he gets the belt first I will.
"I just need to go and do what I need to do and then I can sit down, and everyone can be happy, because obviously nobody's happy with me standing up.
"I'm just saying, why don't you let me fight for the title! And in February or March, there's a good chance that might happen."