Interview: Keith Duggan talks to an impact substitute who will start hisfirst Six Nations game in Cardiff

They say you never forget your debut and so in many moons to come, it will be Leo Cullen's distinction to savour an affair that will hopefully be remembered as the game before the biggest game in the history of Irish rugby.

Funny times, these. The Irish team has taken to imposing fines for the mere mention of E******, their feted and perhaps fated opponents of Sunday week.

Privately and publicly, they are immersing themselves in all things Welsh. They are stopping short of getting Brian O'Brien to dig out his old Shirley Bassey LPs, but only just. Across the country, there is the sense that people are wishing Saturday's game in the Millennium Stadium away, that in a strange way it doesn't count.

Given the respective positions on the Six Nations table, such blasé confidence is probably understandable, if a thoroughly new sensation. But it is an added danger to this team, warding off the general sense of complacency. Such is the backdrop to Leo Cullen's first full Six Nations cap for Ireland.

"It is a great opportunity for me," agreed the big man after yesterday's press conference on the outskirts of Dublin.

"Obviously you dream of playing for Ireland and this is a great time to be involved with the national team. At the same time it is a great pity and very unfortunate for Gary Longwell that he was forced out as he is really on top of his game at the moment and, like, I've had just a few brief runs."

True, his last four appearances have been as a replacement after his first full cap against the Fijians in the autumn but there is something reassuring about the emergence of Cullen's angular 6ft 6in frame for a limbering-up session. Despite his callow years, the Blackrock College alumnus has demonstrated a wise and cool head and proven himself a reliable and effective option in the line-out.

He looked utterly unruffled in entering a taut and highly physical battle of attrition against the French at a crucial period. Shane Byrne, who has developed a pair of Eric Bristow wrists to complement the mullet, had no hesitation in throwing to Cullen from the outset and he seemed to adapt to the tempo and demands of the game instantly.

"Yeah, well, I have been happy enough to get a few runs all right," Cullen shrugs.

He shares the modest and implacable demeanour of Gary Longwell, the man he replaces. That said, being named on the team carries its own duties. Cullen is the latest player Eddie O'Sullivan and company are blooding in what has been a terse and exciting campaign to date. Thus far, all have come through with flying colours and when the Irish coach asserted that he had absolutely no worries about Leo stepping into the breach, you believed him.

"Leo has done well when he has come in for 10 and 20 minutes stretches and has shown a good work rate. There is no real drama when it comes to his selection."

Still, it is a first Six Nations cap. It matters.

"Yeah, I'm more nervous already," he said. "When you are on the bench, it is that little bit more relaxed because you don't know when you will enter the fray. It's certainly going to be a frenetic time for me coming up to the kick-off on Saturday, I am sure. And I will be nervous but you just have to deal with that."

The last person likely to lose big money on E****** fines over the next few days is Cullen. He won't be able to get Saturday out of his head. Tables don't matter. Reared on Five and then Six Nations weekends, Cullen can't but think that Wales in Cardiff is still the theatre of dreams when it comes to rugby.

"Last time out in the Cardiff Arms or the Millennium Stadium as it is known now, they had England and I really felt they dominated the game for long periods which is a great tribute to them because England are the number one team in the world at the moment. I suppose it comes down to the fact that if we underestimate Wales, it will be at our peril this weekend."