Sideline Cut:Where will the journey end for Floyd "Pretty Boy" Mayweather? Tonight, the self-styled brashest boxer on earth will be where he wants to be, casting his light and mesmerising style and message all around the world as he goes toe to toe with Ricky Hatton in a fight billed, deservedly or not, as one to compare with anything the last three decades have offered.

If Floyd's crass and unapologetic rampage through boxing's lighter divisions continues, he will cut through Hatton, the archetypal pale and no-nonsense Lancastrian with the floppy hat and deadpan delivery, when they meet in Las Vegas tonight.

Two cultural universes will collide when the pair meet for the bragging rights and possession of the WBC welterweight title and the acclamation of being branded the "best pound-for-pound fighter" in the world.

While Mayweather's upbringing bears comparison with many of the nihilistic stories that cram boxing literature, this scion of a pugilistic dynasty has displayed shrewdness and mental discipline his father and uncle never had. Mayweather now wears like a badge of honour the basic facts of his early days in the working-class Michigan city of Grand Rapids, when his father served time for drug dealing and his mother was an addict on the brink.

He came through that and he has seen things. In acquiring his flawless 38-0 record, he studied the hype game and manipulated it to suit his natural abrasiveness and confidence. He has borrowed something from almost all the originals in boxing.

There is the faintest reminder of Ali in the boastfulness, albeit without the charm or the self-deprecation or the interest in others. There are echoes of Don King in his more grandiose pronouncements. "I took the hard road," he crowed before his bout with Oscar De La Hoya. "What's done in darkness will soon come into light."

Mike Tyson, of course, was also fond of quasi-mythical statements. And from the former heavyweight anti-hero Mayweather has borrowed the capacity for icy, bullying stares and trash talking but is way more controlled; there is no sign of the instability that marked Tyson's more psychotic episodes.

Mayweather treated De La Hoya with the same blase disrespect he has shown all opponents, but his admiration for the Mexican-American's boxing promotions business was such he has already begun to imitate it with his own enterprise.

The Mayweather refrain is an old one, the boast that has been repeated down the decades: I am the greatest. It is, of course, Ali's line but it is Mayweather's belief, and as he has pointed out, he has mown down every opponent and now seeks a world title in his fifth weight class. And what is more, he has done it on his terms: not for him the huckstering front man and dubious deals and canny money men who will disappear as soon as the feet begin to slow and the alchemy begins to leave. Mayweather has already spoken of his plans to own a casino.

The dazzling nights in the ring are not the apotheosis of the American dream for Mayweather, maybe a fast track toward it. He is young and Motown handsome and talks in hip-hop slang and has a furious, urgent point to prove to the world. And though he seems to revel in his unpopularity, there is something magnetic about him. Already, the footage of his jump-rope routine, where he showboats for four minutes with the magician's sleight of hand and footwork so casual and tricky that at times it is impossible to see the rope, is becoming classic material. The footage was filmed in a gym and a few stand watching, paying homage as Floyd does what comes most naturally: puts on a show.

Hatton's world and personality are as far removed as can be imagined. Pretty Boy is ushered to the ring to the hip-hop serenade of 50 Cent; Hatton had our own Big Joe Egan carry his title belt into the ring of late.

Hatton counts among his pals Wayne Rooney from Manchester United and Ashley from Coronation Street and his cultural references include the Butty Box cafe and holidays in Blackpool, where, as he reminisced in a recent interview, he was once persuaded to join Ray Lewis and the Drifters on stage for a live version of Under the Boardwalk. "Stone cold sober," Hatton added for effect. "When I had 12 pints of Guinness in me, I'd have no problem."

The singer Morrissey, another Manchester icon, has landed himself in trouble of late by commenting on the influx of other cultures while lamenting the disappearance of the England as portrayed in vintage Coronation Street or the works of Philip Larkin or Alan Sillitoe - a slow-changing place of set traditions and values and locality and accents impervious to the centuries. He might be reassured by following Hatton, a young man with a burning sense of place and community and a localised, defiant swagger reminiscent of the Gallagher brothers of Oasis fame.

Hatton's formative experience means he could never allow himself to indulge in the studied mythmaking that comes so easily to Mayweather. Such vanity would go against everything Hatton believes in, and he finds the American's way of living as preposterous and laughable as Mayweather finds Hatton plain and down-at-heel and sadly lacking in the gleaming accoutrements that come with having made it to the top.

Hatton, though, has the one weapon that eludes Mayweather: a tangy Mancunian wit: "If there was such a thing as reincarnation, Floyd would come back as himself." As boxing put-downs go, that was lights out before you even hit the canvas.

Above all their sportspeople, the English seem to revere and respect their boxers most. It could be that the press and public are exaggerating in their own minds the mystique and importance of this night; regardless of the pay-per-view records expected to materialise in the early hours of tomorrow morning, this does not seem like a fight that is thoroughly gripping both sides of the Atlantic. But at least it brings together two boxers with unblemished records at the peak of their powers and with the mental acumen to not only deal with but control the gaudier excesses of promotion and hyperbole that govern the fight game.

Whether Hatton wins or loses here, there is the sense the man is just too grounded and clever to get ever get chewed up in the machinery of big-time fighting or sporting celebrity. He has one lifelong advantage over his opponent: he knows where he is from. It is a quality easily detectable too in John Duddy, who will pack out the King's Hall in Belfast tonight.

And that is the one fear admirers of Mayweather might hold: that he is dislocated and knows no other way except bigger and louder; the problems will come when the world stops listening.

Tonight though, in classic Vegas tradition, two men with nothing in common besides their unstoppable zest and courage and skill in a boxing ring will meet for the right to be called the undefeated. Rarely now in big-time boxing do these globally advertised encounters offer the substance and heart to match the hype. But this is an exception, no matter whose arm is raised at the end.