"God, no, " he says, with a soft smile. "I didn't see it until the book was finished, and then I thought 'Why did they have to put something like that?' If I was a Roy Keane, a Liam Brady, a Johnny Giles, a Ronnie Whelan, I'd have been insulted. But I'm sure those fellas would look at it and say 'It's obvious Paul didn't want this on the front of his book.'

No, Jesus Christ, in some ways I think that might put people off buying it. But the people who know me, they know I wouldn't say something like that. Jesus, not in a million years." And yet there are plenty in Ireland who do not consider it to be hyperbole.

Even when he was fuelled by alcohol, McGrath was by any standards an outstanding player, whose career-defining performance was arguably in the World Cup in 1994, at Giants Stadium in New Jersey against Italy. McGrath was inspirationally obdurate at the heart of the Irish defence. And yet after Ireland's famous 1-0 victory, he found himself unable to celebrate.

"I was sitting at the back of the bus, looking through the tinted glass, watching the Irish supporters all delirious, yet I couldn't tap into what had just happened." It wasn't the first time. He'd had the same feeling of detachment following Manchester United's 1985 FA Cup final victory over Everton.

"I've watched the video back, and I can see myself sort of half jumping up and down, thinking 'I wish this was over.'" I tell McGrath that, coincidentally, Mark Hughes once told me exactly the same thing about the same match, that while the likes of Bryan Robson and Frank Stapleton celebrated, he felt left out. His eyes open wide. "Really? I had no idea Sparky felt the same way." It's rather poignant, I venture, to think of these two hard men wandering around the Wembley pitch, at a moment of such collective triumph, feeling lonely. McGrath laughs. "Yeah. . . I can't speak for Sparky but for me it was a self-esteem thing, the idea that I was gatecrashing someone else's party. All I could think was 'Let them get this song out of the way, then I can scurry back to the dressing-room.'" Low self-esteem has always been at the core of McGrath's problems, and you don't need a degree in psychoanalysis to trace it to his childhood, maybe even to his conception.

In 1959 in Dublin his mother, Betty McGrath, became pregnant by a Nigerian medical student. Betty felt certain that her father would have gone doolally had he found out, so she left for England, ostensibly to find work. Paul was fostered and when his foster parents could no longer look after him, sent to an orphanage.

There he was beaten when he wet the bed, to the refrain, "Dirty little nigger boy."

Years later, Ron Atkinson used the same horrible word about Marcel Desailly.

McGrath loved playing for Atkinson, both at Manchester United and Aston Villa, and admits to thinking the world of Big Ron, so I ask him what his feelings were in the wake of the Desailly episode?

A pause. "Well, Ron's old school, I have to say that. But Jesus, he's one of the furthest men away from being a racist."

A further pause. "He might say the odd word that makes you think 'Jesus, what's happening here?' He had this thing in training, where he'd say 'It's the coons against the rest.' But we'd just laugh about it. And the so-called coons had a good team - me, Yorkie (Dwight Yorke), Dalian Atkinson, Cyrille Regis - so we were delighted. Never once would any of us have taken exception.

What he said about Desailly, that's something you shouldn't be saying. But I grew up with all that. There were only about four black people in Dublin back then, and I got into so many fights when things were said in malice. If Ron had ever done that, I wouldn't have taken it from him. But I always thought he had a kind of fondness for the black lads." McGrath laughs gently. "I hope that doesn't go out the wrong way."

He need have no such worries about his book, which offers very little scope for misinterpretation. A life littered with broken relationships, suicide attempts and a dependence on alcohol so chronic that, unable to find any vodka in the house, he once downed a pint of Domestos; it's pretty unequivocal stuff. Was it cathartic to write? Or, given that the Irish journalist Vincent Hogan did most of the writing, to read? "Well, yeah, but when I read the proofs back I thought 'Jesus, what sort of a human are you, that you can do these sorts of things?' I think even a few people close to me were shocked.

I was sick, which is not a great excuse, but it's the only one I've got. I'd get depressed, then heap alcohol on top, which is a depressant itself. And I ended up doing some of the most ridiculous things imaginable considering that I have [six] children. I'm blessed that they're being brought up in a great manner."

The final paragraph in the book is a comment from his son Jordan, saying: "He shouldn't carry any guilt over what we've been through.

Because we don't carry any burdens. He's a good dad. It's still a really, really proud feeling just to be walking down the street with him." McGrath nods. "Yeah. . . that's fabulous for me, to read that, to know they're still in my corner."

So what now? McGrath is living near Wexford, working hard at being a recovering alcoholic. He is receiving help but is sparse with the details.

"It's going brilliantly, but it's the old cliche of a day at a time. I honestly don't know if I've had my last drink. It's been a few months now, but while I was still playing football I once went a year and four months [on the wagon], which is as well as I've ever been, so I know what the prize is."

There is no sign that his alcoholism has wrought any physical damage - he looks lean and healthy - but financially as well as emotionally, it has been costly. He is not a particularly wealthy man.

"Which is OK. I like the simpler things, and I don't really want for anything. But I have commitments back in the UK, and I need to work. I'd love to get back into football. It's the only thing I know anything about, really. I got involved with Waterford [United] there for a short time, which was just a joy." Maybe some farsighted Premiership club will offer him a coaching job, I suggest. "You never know. There might be someone who thinks it a good idea to bring a hooligan to the club."

McGrath's conversation is studded with these put-downs of himself, which suggests that self-esteem is still an issue, a paradox in someone held by so many in such mighty esteem.

In the book, Ron Atkinson says that McGrath the player was better than John Terry or any of the current crop of top central defenders, a compliment that pleases McGrath, in his resolutely modest way.

"I'm like everyone. I love it when people appreciate what I do. I sometimes think that I wasn't everything I am made out to be, but then I read that and think 'Yeah, I wasn't a bad player, I might even have been a good player.'" McGrath is upbeat on the subject of Roy Keane's managerial prospects. "Like everyone, I was surprised [when Keane went to Sunderland]. I thought he might take a good chunk of time out. But I think he'll definitely be successful.

He has a winning temperament, and it rubs off the people around him. I'm a friend of Mick McCarthy's but during the stuff in Japan [in 2002] I came down on Roy's side. That was anyone's World Cup to win, and there was no need to send him home. If I'd been manager there's no way I would have sent Roy Keane home. Maybe five or six of the other lads." A little chuckle.

"No, no, I'm joking." I wonder whether he is, entirely.

"It's interesting that Roy's now the one in charge of the discipline, " McGrath continues. "Of course, you never know which players will succeed as managers. I'd never have thought Sparky would do so well. He was the quietest fella when I first knew him. When he finished playing I just thought he'd have his business or whatever. . . it's good to see one of the quieter men going well." Let us hope that we can one day say the same about McGrath.