There was no cabaret act at yesterday's press conference. Mick McCarthy played it straight and snappy and got on with business.

He named no team, gave no hints as to his thinking and ventured into the realm of humour just once. Asked about the problems of thin air he cast an eye over the press crew lovelies and announced that there was a lot of thin 'air there. Then he put his poker face back on and as such it was vintage Mick McCarthy. No frills, no gimmicks. Just the man you see before you.

His Iranian sparring partners, so inventive in their extemporaneous teasing on Tuesday, were disappointingly subdued. Not one question. Even they realised that there are times in a man's life when the only respectful thing to do is to allow him space.

For Mick McCarthy this afternoon will determine much about the rest of his professional life, much about how people judge him and how he rates himself. He has done a wonderful job in guiding a long-shot team from the middle of the world rankings to the verge of a World Cup but he knows that in terms of what he expects from himself nothing but success today will suffice.

In a career which took him from his home town team of Barnsley to Manchester City, Glasgow Celtic, Olympique Lyon and, finally, Millwall as a player and then a manager, McCarthy has taught himself to win and conditioned himself to expect nothing less.

His character was best studied through the prism of an international career which not only spanned eight years and 57 caps but saw him secure a centre half spot in a team crawling with more exalted practitioners of the same arts.

And he never let anybody down. Although still not celebrated as one of the great Irish defenders, the team's record with McCarthy at the centre of defence was remarkable. Those 57 appearances brought 34 clean sheets, with just one goal conceded on 17 other occasions.

In just six games did teams score twice against Ireland and just once, back in 1984, did a team (Denmark) put three in against a team with Mick McCarthy in it.

It was a record of a man who forced his way to the top through power of will and through sheer hard work and professionalism. Although the lazy rap on McCarthy is that he is a stubborn Yorkshire man cut from the same cloth as his obdurate predecessor the secret of his success has been his ability to learn and his reluctance to behave as dogmatically as he sometimes sounds.

He came into the job with ideas about playing sweepers and experimented wantonly with the traditional 4-4-2 system. He announced that only players getting regular games at their clubs would be considered, Yet his native pragmatism won out. He went back to 4-4-2 because it worked best, he began picking players who worked most efficiently within the systems he devised.

Some of his harsher detractors in the early years accused him of crimes ranging from naivety to stupidity, but those who watched closely saw a man keeping several plates spinning at once. He was left with the task which Jack Charlton shied away from, that of easing out many of his old friends and colleagues. Few of them went quietly and the process hurt McCarthy personally more than he has been prepared to admit publicly. Meanwhile, he set about bringing in his own players and stood by them through thick and thin. The criticism came thick, the success thin.

Most important for anyone watching for green buds was the team's performances on big occasions. Management is about that intangible, the X factor, about whether or not you can motivate fellow professionals to go out onto a pitch and lay down their guts for you. In places like Bucharest and Belgrade his young team did just that. They lost but they did so narrowly and playing with guts. They slipped up also against lesser teams to howls of derision from McCarthy's critics.

He pushed on unbowed. You can't see Mick McCarthy as a fan of kitsch musicals but he often comes close to quoting Julie Andrews to the Von Trapp kids. "I have confidence in confidence alone and besides which, you see, I have confidence in me."

He speaks often about the pleasures of playing and the time he spent pining for the joys of a career which brought him success and adulation beyond the imagination of anyone who saw his early forays into professional football with Barnsley. Yet players and managers share one experience always, those helpless hours before a game - those times when you wonder if your skills and abilities will betray you.

This week has been one long version of that introspective time for Mick McCarthy and he has scarcely flinched. The face is a bit tighter, the press conferences a bit more terse, but he is afraid of nothing. He gets up this morning on another one of those days which advertise themselves as the first day of the rest of his life.

"People often ask me what have I learned," he said yesterday, "from defeats in places like Brussels and Bursa and they are surprised or they laugh when I can't tell them. And I can't. It's inside me. It changes you inside. You become what you are. All the experiences go into making you what you are. I can't say what I learned but I know I changed. I know I am a better manager now and we are a better team now."

This afternoon he puts out a team which will be without Roy Keane, Steve Carr, Damien Duff and probably Niall Quinn. Four of his five best players gone. So he'll send out a lot of young fresh faces onto a field where players can't hear themselves think. And win or lose they will run themselves into the ground for him and for their country. Firstly for him, though.

"We'll go out there and give it everything. We all want to do it for ourselves as a group. And then we'd like to put a smile on everybody else's face of course."

That has been the secret triumph of Mick McCarthy, the struggle, the transition, the alchemy of taking an ailing old team and making it into a promising young team, forging them into a group who see themselves battling the world. Win or lose he deserves our congratulations. The struggle should be enough, but it's not, not nearly enough for an army of impatient fans, for a waiting media, for the players themselves and most of all for Mick McCarthy.