There is an air of mystery about what is going to happen Saturday night in Nuremberg when the largest heavyweight champion in boxing history meets the loudest heavyweight challenger in boxing history. Or should we say the “loutest?’’

A lout is defined in several ways by most American dictionaries. One is “a big, clumsy…person.’’ I give you WBA heavyweight champion Nikolai Valuev. Then again, a lout is also defined as “a person whose behaviour is offensive to others…see jerk.’’ I present WBA challenger David Haye.

Whether you accept either definition or both as applicable to these combatants, one thing is beyond much debate – Big Man gonna have his chin tested this time.

Big Man, of course, is the 7-foot, 325-pound Valuev, a fighter long seen as a circus act in the expanded image of Primo Carnera by many in the sport and nearly everyone outside of it. No one suggests Valuev has been the beneficiary of some pre-arranged victories, as was allegedly the case with Carnera, but certainly no one would dispute that he has not greatly benefitted by towering above his opponents and using his enormous, 85-inch reach and the ability it gives him to grasp a man and clutch him to his breast until he disappears into his considerable body hair to his great advantage.

Occasionally he will land a lengthy but mostly pawing jab but it arrives ponderously, moving forward so slowly at times it seems the jab itself is undecided about how to proceed. As for combinations, well, Valuev will never be accused of throwing punches in bunches.

Yet somehow he has won 50 of his 51 fights, knocked out 34 opponents, twice been awarded the WBA title he now holds and defeated two-time WBA champion John Ruiz twice as well as belt holder Sergei Liakhovich and a depleted version of Evander Holyfield by majority decision on a night when one guy looked slow and the other guy looked slower.

This has led Haye to disparage everything about Valuev calling him, in his kindly moments, “a freak show,’’ “a human circus’’ and a “monster’’ while appearing on the front of the British boxing magazine Boxing Monthly returning a Winston Churchill-like V for victory sign being waved by Valuev with only half that sign in response.

To his credit, the 36-year-old Valuev has declined to respond in kind. Generally he is mostly mute at public affairs, having grown wary long ago of a media horde that looks at him as a fictitious fighter and a clown act. He has grown weary of questions about his height, his early days in Russia when he was transformed from a middling basketball player to a less than elegant fighter and seems to have little interest in discussing much of anything else, although he will talk about his poetry and his love of reading Tolstoy, H.G. Wells and even Sherlock Holmes mysteries.

As for Haye, Valuev simply promises him the same thing he has promised all his predecessors. He promises he will be surprised once he is actually in the ring that Big Man can fight better than advertised.

Frankly, that wouldn’t take much but he will not be lured into some slugfest by Haye, who believes he has superior speed and punching power and his 91.1 per cent knockout rate (22-1, 21 KO) would seem to support that argument even though all but two of those knockouts have come against cruiserweights when he was the undisputed champion of what has become the junior heavyweight division (guys like Rocky Marciano and Floyd Patterson, among many others, would be cruiserweights today).

Valuev fights in a surprisingly cautious way for such a big man, a boxer who lacks great movement but does possess an apparent healthy respect for engaging in hand-to-hand combat. If there is anything to be wary about – beyond body hair that needs to be brush cut – it is his straight right hand and an uppercut that can do damage to a guy like Haye, who has a bad habit of leaning forward on the inside.

In an effort to expand upon his advantages, Valuev has changed trainers and is now being handled by the Russian Alexander Zimin, who claims Valuev will throw “many more punches’’ than he threw against Ruiz and Holyfield. Well, to be brutally honest, in some rounds that would barely require he get to double figures so time will tell but it shouldn’t require much additional planning.

Yet for all his demerits, Valuev has never been knocked off his size 18 ½ feet and that is a skill in itself that has to be acknowledged and admired. Not by Holyfield or Ruiz or Jameel McCline or Larry Donald or Monte Barrett (does everybody have to fight Monte Barrett by the way?) or even by the only man to defeat him professionally, Ruslan Chagaev.

Haye says he will be the first, doing it not with one big shot but with speed and a relentless body attack that will weaken the Goliath of St. Petersburg (that’s the one in Russia not Florida, folks) until he tumbles to the canvas the same way George Foreman did against Ali, a victim of his own body weight and a pace with which he cannot cope.

Asked about this recently Valuev was expansive enough to say, “Fine. We’ll see.’’

Yes we will, if we make the choice to pay $24.95 for the pay-per-view distribution in America, a choice that would not be recommended even for aficionados of the sport of boxing because, frankly, there won’t be much boxing going on Saturday night in Nuremberg. What there will be is the biggest trial there since the World War II war tribunals in 1945-46 but this will be one of a far different, and far less important, nature.

On trial this time will only be a sport, the sport of heavyweight boxing. It is a sport that has itself become a circus act but not a high-wire one filled with drama. Rather it has become a clown show where a giant with limited abilities but boundless body hair faces a cruiserweight who agreed to and then ducked out of fights with both of the Klitschko brothers after much loud fanfare concerning what he would do to each of them to grab a chance at what he figures is an easier belt to win.

One of them will leave with that WBA strap, for what it is worth. Perhaps it will be the breath of hot air that is David Haye. Perhaps it will be Big Man. Either way, heavyweight boxing will remain what Nikolai Valuev has been unfairly accused of being. It will remain a circus, not a sport.