'Why be hateful to a guy you're going to make a fortune with?'

Roy Jones Jr has gone down into the darkness so many times that he carries the look of a man about to return to his most familiar place on earth. He might never have really loved the murky risk and raw violence but, having won over a hundred million dollars between the ropes and also been knocked cold and senseless, Jones approaches his fight against Joe Calzaghe at Madison Square Garden on Saturday night with a profound understanding of boxing. The once brilliant but now faded virtuoso of the ring knows how much this savage old business retains its capacity to reward or maim in equal measure.

"I'm a realist," the 39-year-old drawls with a sly little twitch of his lips which is too cool to be called a smile, "and so I really don't know what is going to happen between me and Joe. I don't know what tomorrow holds. None of us do. We got to wait and see what God has planned."

Jones has always boasted of his religious serenity before fights; and it is a claim he now bolsters further by stressing the significance of Calzaghe and him seizing promotional control of their lucrative contest. "That's the beautiful thing about this fight," he exclaims. "Joe is the first fighter I'm facing that don't have a promoter. He got rid of Frank Warren and so this is the first time two super fighters have got together and put on an event this special with not a single promoter in sight. There ain't no Warren here, no Don King, no Bob Arum, none of them guys. That's a huge victory for both me and Joe.

"So I don't know what will be the bigger accomplishment - me winning and handing Joe his first loss or the fact that we changed boxing history by promoting it ourselves. Which is the bigger story? And what might God have planned for me? Do I get one or two victories? I just know me and Joe already got one big win each by making this fight."

As a further example of the way in which boxers have tried to take charge of their careers, following the lead of Oscar De La Hoya, who is America's most famous current fighter and the head of its new promotional powerhouse, the Jones-Calzaghe extravaganza provides another intriguing landmark.

"Joe is a whole lot easier to deal with than Don King," Jones chuckles. "From the start we said we split it down the middle, 50-50. He gets his half, I get mine. Never had to play hardball with Joe. We just started texting each other, saying let's make this fight. We made sure we put together a real good fight and a real good situation for both of us.

"That's why there's no reason to talk bad or start swearing at each other. Why be hateful to a guy you're going to make more money with than anyone else in your career? Of course you want to beat him but I don't want to say I hate Joe's sons - and I sure don't want my sons to hate Joe. Why should they? Joe's a great fighter and a pretty good guy."

Yet beyond the shift in promotional power the grim old dangers of boxing remain. Calzaghe, a grizzled veteran himself at 36 and still undefeated after 45 bouts, is too smart to be seduced by Jones's friendly façade.

He has already suggested that, for all the warm words, Jones will "want to rip my face off" in the ring. Calzaghe, in turn, promises another troubling night for a fighter who once legitimately called himself the best in the world - especially in March 2003 when Jones completed his dizzying rise from being an outrageously skilled middleweight to becoming the WBA world heavyweight champion by outclassing a far bigger man in John Ruiz.

"I know it's going to be tough," Jones concedes. "Joe's got 32 KOs so I know what he can do. Don't worry - I'm no fool."

Anyone who saw Jones being knocked out by Antonio Tarver, or left stretched on the canvas for a distressing five minutes after taking a withering punch from Glen Johnson, will not need any prompting to feel some concern for an ageing fighter. He might have suffered only four defeats in 56 fights but memories of those two shocking nights, coming within a few months of each other in 2004, cannot be easily shaken.

"I know why you keep talking about those two defeats but I'd just come through all the devastation of moving back down from heavyweight, of losing all that weight. And one-punch knock-outs can happen to anyone. Tarver got lucky. He never beat me up or nothing."

And yet Johnson, a hardened pro rather than a boxing genius, doled out a painful beating for nine rounds - before smashing Jones into unconsciousness. "I was done," Jones grunts. "The doctor afterwards said I was so dehydrated. I had taken so much out of my body to make the weight I had nothing left. But the interesting thing about that fight is that I have an aunt in Pensacola [the Florida town where Jones has lived all his life] and I talk to her more than most people. I told her before that fight that I wouldn't be surprised if I got knocked out. I never felt that before or since. But God sometimes brings turmoil down on you to test your faith. I felt that happening then."

Jones has won his last three fights, the most recent being an easy victory early this year over the hopelessly outgunned Felix Trinidad - who used to be an outstanding welterweight in the late 1990s. That lopsided win meant little, as even Jones admits. "I loved it but Trinidad wasn't even a legitimate middleweight - so how could he face Roy at light-heavy? C'mon!"

Logic suggests that Calzaghe should win comfortably but a more insidious feeling persists that Jones could yet dredge up some of his old ferocious dazzle. He still carries a hard edge, despite his effusive praise for Calzaghe, which harks back to the trauma of his childhood.

Jones once showed me the patch of ground in Pensacola where his father, Roy Sr, who trained him throughout his early career, "used to whup me with a plastic pipe or a water-hose, sometimes a belt, to make me fight back, always asking, 'Well, boy, you a kingpin or a participant?' I always said the same, 'Kingpin...' "

At least he and his father, after their infamous break-up when Big Roy shot Little Roy's pit-bull more than 15 years ago, are speaking again. "I had to leave my dad then. Once God said 'Go', I headed for the woods but that's a long time ago. Things are cool now."

And what about those notorious training sessions his father made him endure as a young boy? "I thank him for it," Jones says, "because that made me the person I am. I wouldn't want to go through it again but it made me strong. My dad sacrificed his relationship with me so I'd be stronger for it. But I could never do it to my kids - I like to have a happy relationship with them. If I could I have a relationship with my dad like Joe has with Enzo [Calzaghe] it would be great - but me and my dad don't work that way. And we never will."

Jones looks at me with an unblinking gaze that transcends regret. And suddenly it becomes possible to believe some of that past darkness might yet drive him on to one last supreme effort against Calzaghe. It also makes it seem ludicrous that his shaven-headed, bull-necked manager should then threaten me after Jones and I have discussed his more pained reaction to the fact that cock-fighting has now been banned in neighbouring Louisiana.

"They've made it a felon to drive from Florida to Louisiana with any fighting birds," Jones sighs, "so I've had to get rid of most of my chickens. I only got about a hundred left now, which I just keep for colour and breeding. I love those birds as much as anything. I don't fight them no more but people don't understand fighting is in the nature of those chickens. I think it's ridiculous but I have to move on."

Jones is a law-abiding citizen who has abandoned cock-fighting for good - but two of his management team come down hard on me after our interview has ended. All kinds of trials and tribulations are promised should I even mention that Jones and I had discussed his enduring love of watching one rooster do battle with another. It is mildly bemusing for Jones has argued throughout his career that he has learnt more about boxing by studying his strutting birds than watching grainy footage of any great pugilist from the past. Jones himself is blissfully oblivious to the heavy-handed exchange and he continues talking about his beloved chickens in an adjoining room.

He does not sound much like a man in need of protection; for a cold and dark fighting heart still beats inside him. And so, against all odds, Jones looks set to give Calzaghe a long and brutally searching night at the grand but bloody Garden. Joe Calzaghe v Roy Jones Jr is exclusively live on Setanta Sports 1. Details on setanta.com