Alan Quinlan: 'Psycho' Paul O'Connell was rugby's answer to Roy Keane
Kyle. McBride. Gibson. O'Driscoll. And now Paul O'Connell. Does his name deserve to be up there among the greats? You bet your bottom dollar it does. Just look at his CV - a three-time Lion, three-time Six Nations winner and two-time Heineken Cup winner. Was there anything he didn't do?
Think about all his great days in a Munster shirt, particularly that performance in the 2006 Heineken Cup semi-final against Leinster. Think about how he delivered time after time for Ireland in their Grand Slam year. Think about what he did last year - his last as a professional.
Showstopper to the last, he crowned his final Six Nations season with the trophy in his hands. The best there has been? Victor Matfield thought so: "Of all the second-rows I have played against, Paul O'Connell was my toughest opponent."
It's some compliment. As was Dan Carter's. "World class," was the New Zealander's summation of Paul. Coming from him, that's quite the statement.
For years I sat next to him in a dressing-room. He wore number five. I was six. Often he'd give a rousing speech which would gee us all up but sometimes he managed to get us going with just a look.
We'd sit no more than a foot or so apart. I'd often be nervous. But he never was. Yet he always had this knack of saying the right thing at the right time. He'd turn, catch my eye, and glare. "You ready?"
After that, I was.
He was a brilliant team-mate - and not just because he was there to look out for you. He'd set the tone. If training wasn't good, he didn't shy from telling you or anyone that we had to sort ourselves out. Some of his comments could cut to the bone.
Often he called myself and Ronan O'Gara a pair of grumpy f**kers. In reply, we christened him Psycho. And the nickname stuck. Until one day someone called him Keano and that seemed a better fit.
And in so many ways he was like Roy Keane. Driven. Passionate. A leader.
There was a touch of madness about him on the week of big matches - as there was with so many of us. You kind of have to be that way when you are striving for perfection, and when you know that on match-day, all sorts of pain can visit you.
I've seen him hurt. And play on. At different stages of his career he had a broken arm, concussion, a dislocated finger. Yet and on he went. Madness. But he did it.
And he did so much more besides. In the Munster and Ireland camps, he had an innate sense of noticing when someone was feeling uncomfortable or a little unsure. And he'd grasp the chance to make them feel welcome, a point Mike Ruddock made earlier this year.
"I always respected him as a player and as a man," Mike said, "but it was only from talking to Rhys (his son, the Ireland flanker) that I really got to know about him. He made Rhys feel part of it with Ireland. The man has a touch of class." No one doubts that.
Nor do I doubt what he'll do next. A holiday would be a good idea because when you are an elite athlete and striving to be the best you can, it is a strain. Mentally you are tested and after a number of years, you need a rest.
Yet knowing Paul, he won't rest for long. Coaching will be his destiny and I don't subscribe to the view that he needs to serve an apprenticeship because this fella has been leading all his career. He has a presence when he speaks in a dressing-room. The chatter stops. Paul speaks and men turn and look. Their eyes are on his. They take in every word.
He'd be great for Munster. I could see him doing a job there helping out Anthony Foley. And I can see how he'd seek to improve himself because all his career, that was all Paul O'Connell ever did.
He saw young players as a source of knowledge. He'd ask them about their training and diets and see if he could borrow some of their ideas.
You see, what you have to remember about Paul O'Connell is that he was not the most naturally gifted player there has ever been. But he wasn't just willing to learn, he was desperate to get involved in the self-education process.
That was why he'd line up beside the younger, fitter guys in the squad on training days and push himself to the limit. It was why when there was a skill session, he'd disappear from us, and get in among the silkiest, most skilful players on the panel.
It was why he studied Afrikaans before the 2009 Lions tour to South Africa, so that he could guess their lineout calls.
And it is why I see him coaching - because aside from loving the game, he's a student of it.
And long-term he'll need something massive to fill the void that he is leaving behind. Right now, I have no doubt he will be comfortable with his decision to quit because he will know that his body will not be able to reach the level of fitness that is required for elite rugby.
But a time will come - maybe a few months from now, maybe a year - when it'll hit home. He could be sitting at home or at a match, in a stand, and he'll notice the atmosphere. And he'll remember that buzz.
He'll remember the noise. When you walked out that tunnel and you heard that roar, you got this adrenaline rush that no words can do justice to. And when it dawns on you that you'll never get that buzz again, that is a pain every sportsman goes through.
Yet he'll deal with the grieving process better than most because he can look back without regret. He knows he gave everything he had. And he knows he won some big, big games.
He delivered under pressure and better than anything else, he didn't just get the best out of himself, but out of others too.
At Peter Stringer's wedding last summer, we had a pint and a laugh and a few of us reminded him that he wouldn't have got anywhere if it wasn't for us. And he loved that kind of banter.
For while so many of us may have been on the end of that intimidating stare if we messed up on the training paddock, we were glad of him as a team-mate or a friend when we needed his help.
The guy wasn't just a great player, he was, and is, a great bloke.