Tucker had held that version of the title for just 62 days after taking it from James 'Buster' Douglas when he found himself in a unifying contest against the ferocious young New Yorker who was spreading terror throughout the heavyweight division. It was 1 August 1987, and as Tucker made his way to a ring in Las Vegas, nobody gave him much of a chance.
This week, Tucker read that after one good round he ran like a thief, but it was not that way at all. In truth, he gave Tyson a hard fight, forcing him to rely more on technique than intimidation. Tucker can see that on videotape.
For the rest of it, the 18 months of turmoil that followed, he must rely on images that swirl around in his mind. He can talk you through those all right. 'You know those moments when you first wake and everything comes together? Well I'd lay there and it would come to me like a death in the family, and I'd hope it was just a bad dream.'
Even Tucker's father was cutting him up, selling off so many slices of his contract that soon there was 120 per cent of him out there. 'All told, I think I had 14 managers,' he said this week. 'Can't remember most of their names.'
No wonder that he turned to drugs, and people said he was just another of those who nearly get there. 'It would be embarrassing to tell you how little money I was left with,' he added.
Tucker was sitting sideways on the passenger seat of a van outside Johnny Tocco's gymnasium in a part of Las Vegas that it would be extremely unwise to visit after dark. He was dressed for a stretching and sparring session, and every now and again he sucked on dry lips.
So what about those lost years when it was assumed that he would never be seen in the ring again? The worst of it was that nobody had given Tyson a better fight, asked him more serious questions, until Douglas sensationally defeated him in Tokyo. 'Douglas got what I might have had,' he shrugged, 'the title and the fortune that went with it.'
Since beginning his comeback with a third-round knock-out against Dino Homsey in December 1989, Tucker, now 34, has added 13 straight victories to a record that shows just one defeat and one no-contest in 50 professional outings.
None of those opponents could think themselves candidates for boxing's hall of fame, but no matter, in Tucker's mind they add up to renewed confidence. 'I've straightened myself out,' he insisted. He now has a wife, Kim, and there is a baby on the way. Somewhere along the way he turned to God and Don King, which in King's mind is one and the same thing.
Tucker insists that he now owns most of himself, coming up with a curious figure of 84 per cent after a whispered consultation with his head trainer, Roosevelt 'Stacey' McKinley, a balding, loquacious man who is not slow to point out that Lennox Lewis has yet to be asked some serious questions in the ring.
If there is a hint of desperation in the chant of 'London Bridge is falling down' that McKinley leads whenever British visitors are in the vicinity, it does not detract from the importance of his observations. 'Lewis hasn't been in a fight where he has been hit hard on the chin and been forced to dig deep. And in the last 18 months he's only had six rounds of boxing.'
Most of Tucker's work is being done under wraps at Tocco's, an establishment that will never be mistaken for a Knightsbridge health club, and predictably he claims to be in the best shape of his life. 'I'm bound to be in better condition than I was against Tyson,' he said, 'because my right hand was broken when I went in against him. Once when I hit him the pain went all the way up to my shoulder. Hey, that really hurt.'
It was nothing to the pain of realising that his father was hawking bits of his contract around boxing to pay for drugs. 'Can you imagine what something like that does to you?' he winced. 'Being betrayed by your old man? That ripped me apart, but he's my father after all, and I've forgiven him. I still love him dearly and he's coming to the fight.'
Perhaps that is as simple an explanation as exists about how Tucker comes to be in contention for the World Boxing Council championship that Lewis gained by decree and will defend at the Thomas and Mack Center here on Saturday. 'This is a new me,' he said. 'None of us can claim to be anything unless we can forgive.'
The pain, as anyone can tell by examining Tucker's record, has been more mental than physical. Before the unhappy days he was an outstanding amateur who probably would have won an Olympic gold medal had the United States not boycotted the 1980 Games in Moscow. He is an excellent boxer whose heart has never been in question.
Tucker looks at the world through steady eyes and believes that he has the beating of Lewis. 'Why else would I be here?' he said sharply when suspecting that he was being looked upon as a vehicle for King's desperation to regain a foothold in the heavyweight division. 'What has Lewis done?' he asked. 'They gave him a title, I won mine in the ring against a man who went on to knock out Tyson. I went all the way with Tyson when everybody was terrified of him.'
Perhaps the stern expression that crossed Tucker's face was more theatrical than anything else, but who can tell?
McKinley cut in to say that Tucker has shown him things he had not seen before. 'Little moves, clever shifts, the sort of things that only come naturally,' he said. 'He's got the stuff to beat Lewis.'
Tony Tucker nodded, and said that he would.