Lennox Lewis, with the quiet dignity which has been the hallmark of his professional career, says losing the World Boxing Association version of the heavyweight title in a New Jersey courtroom recently has meant nothing to the sporting public.

In their eyes he will step into the Madison Square Garden ring on Saturday as undisputed champion. And the 6 ft 5 in, 18 st Lewis foresees only one outcome against his 6 ft 7 in, 18 st undefeated challenger, Michael Grant: a knockout victory.

"I know I am still undisputed champion, with or without the belt," said the Briton, who will be defending only the World Boxing Council and International Boxing Federation titles after a judge ruled that the WBA was within its rights to strip him of its title because he had failed to meet its number one contender, the Don King-promoted John Ruiz.

Where once he spoke of his "mission", which he achieved by beating Evander Holyfield to unify the title, now the 34-year-old champion speaks of his legacy as he contemplates retiring because he believes he is running out of meaningful challenges.

Although Grant is seven years his junior and recognised as a worthy opponent, Lewis is dismissive of his chances. "He's only been in against B-class opponents, now he'll have to raise his game because I am A plus. He has height, reach and strength but he's never been in against anyone like me.

"I feel very confident and I don't believe this fight is going to go the distance. He says he dreams about me and of winning, and his trainer says he will murder me. Well, I'm glad because if he thinks he can win he'll be taking risks. Evander Holyfield has that big old neck but Grant doesn't and he won't have the shock absorbers to take my punches."

"The key to this fight is Lennox's power," said his manager Frank Maloney. "Okay, Grant may be big and fit, but he is not good enough. He is overrated and Lennox will destroy him."

The American boxing writers who spent years rubbishing Lewis have changed tack to the extent of voting him their fighter of the year. It is acclaim he has long craved, and his demeanour is that of one revelling in his position at the top of the pile and one who has earned the right to say he is the best.

He turned to the question of his legacy, saying: "I won't be around this sport much longer. I looked at the situation with Riddick Bowe. When he won the undisputed title, who did he go up against? Michael Dokes and Jesse Ferguson: no-hopers. I didn't want that.

"I'd like to meet Mike Tyson but I don't think he wants to fight me. So I just have to be positive, fight the best and show the world that an outsider can work his way in, avoid bad promoters and be champion."

When fighters talk of imminent retirement it can be indicative of a lessening of desire or a first acceptance of decline. Perhaps Lewis sees the warning signs, but it is more likely he has set his own final target. He has managed to be master of his own destiny in a chaotic sport, and Michael Grant may be about to find out he is simply part of a greater picture.