Ian Borthwick explains why France's leading sports newspaper is taking unprecedented interest in tomorrow's Irish showdown

So the interest surrounding this all Irish semi-final is without precedent in the history of Irish club rugby? The fact that my employers, the Paris-based national sports daily L'Équipe sent me to Ireland for five days to cover the build-up is also without precedent, but it is also the measure of the success of Irish teams in the European Cup.

And given the way that, in their respective ways and with their respective qualities, both Munster and Leinster have captured the imagination in France, interest "chez les Français" has also reached unrivalled levels.

Even five years ago a similar match would have elicited virtually no attention from the French media, and L'Équipe would undoubtedly have just taken a minimal match report off the wires.

But the ever-increasing profile of the European Cup (sorry, for professional and gustatory reasons I am unable to use the H word) and the remarkable progress of Irish teams, means that not only did yesterday's paper carry a major feature on the cultural and historical background of Leinster v Munster, but we will have not one but two journalists at Lansdowne Road tomorrow reporting on the event.

Ever since the quarter-finals, however, the French have been keeping a weather eye on the proceedings at Cork, Limerick and Dublin and not necessarily in that particular order. The power of Munster, their realism and their apparently simple game plan are nothing new to the French, and their famous defeat of Toulouse in Bordeaux in 2000 undoubtedly marks a watershed in the French perception of the Irish game.

But whereas the pace and flair of Leinster are a comparatively new phenomenon to the Gallic rugby followers, the recent quarter-final trouncing of Toulouse in Toulouse, avec la manière, as they say, was a real wake-up call.

After all, here was an Irish team brimming with confidence and flair, beating the outgoing European champions at their own game. Sure, Toulouse looked physically flat and lethargic as a result of their relentless fixture list, and the fact their top players are still having to play as many as 40 games a year is an aberration that will have to be addressed in the very near future.

But at le Stadium, Brian O'Driscoll and his men showed that sparkling back play, speed of thought, speed of hand and speed of foot are no longer the exclusive preserve of the French.

Despite this, naturally enough, the main focus across the ditch in France this week has been on the Biarritz-Bath match to be played in San Sebastian today.

Biarritz are the current club champions of France and on their day they are capable of playing the sort of rugby that can match the best either Leinster or Munster have to offer. And after the surprisingly early exit of both Stade Français and Toulouse, the Basques are France's only hope of continuing their dominance of the European Cup.

If the French are so interested in Irish affairs, however, it is also because there is a widespread assumption that Biarritz will be playing in the final in Cardiff.

With all due respect to the players of Bath, there are very few in France who believe the Englishmen have a snowball's chance in hell of beating the Basques in the cauldron of Anoeta Stadium.

Bath certainly put up a valiant fight in their dour quarter-final against Leicester, and their effort of denying the Tigers in the final 10 minutes when Bath were down to 13 men was nothing short of heroic. But realistically, their place in the semi-final owes more to the total incompetence of Leicester, and in particular their blinkered outhalf Andy Goode, who ignored a three-man overlap five metres from the goal-line in the dying seconds.

Instead of simply passing the ball for what would have been a certain try and a ticket to the semi-finals, Goode impaled himself on the stout Bath defence, who turned the ball over, and the moment was lost.

It is hard to see either Ronan O'Gara or Felipe Contepomi making such a pitiful decision at such a crucial moment, but the reality is both sides at Lansdowne Road tomorrow will benefit from having world-class playmakers at the helm. They both have their distinctive qualities, and Contepomi has shown recently he has few equals in being able to take the ball to the line and to play in the defence.

O'Gara, however, has another set of trumps up his sleeve and it is no insult to say that in terms of playing for position and putting the ball in front of his forwards, the Munsterman excels at the 10-man game. And when Munster play that way, they do it very, very well.

Which brings us to the old chestnut, the ying and the yang of Irish rugby. In other words Munster's culture of hard-nosed forward play versus the Leinster tradition of fancy back moves. This is what L'Équipe sent me to Ireland to investigate: to establish why one Irish team is famous for its forwards while the other has a long and splendid tradition of back play.

There are, of course, a number of reasons, as readers of L'Équipe discovered yesterday. But at the same time I found that within the teams themselves, there was a desire to avoid the stereotyped one-dimensional image. When I spoke to O'Driscoll last Friday, for instance, he was either being supercilious or he was sick of answering the same question, but he claimed to have no knowledge of Leinster's tradition of back play.

Perhaps he thinks it started with him. "We're not trying to play a particular brand of rugby, we just play what we see in front of us and we are enjoying what we play," he said.

"This season maybe we have been playing a more open sort of game, but with regard to the past, I really don't know. When I was growing up I cannot say Leinster's back play was a feature of my rugby culture."

By contrast, and not surprisingly, Anthony Foley, the Munster captain, had a far more humble and down-to-earth take on it.

"A lot of people are trying to say we play this way and they play that way. But it's not necessarily so," he said. "Leinster feel their first strike is their back line, while for us, at times, our first strike is our forwards. That's all, it's not taking anything away from Leinster's forwards or our backs, it's just aimed at where you feel you get your best reward."

Refusing all clichés, the Shannon number eight also resolutely resisted any attempt to see the game as a duel between rural ruffians and city slickers from Dublin 4. "Its too simplistic to say that," he said. "I think you'll find we're a bit more sophisticated than people think."

Whatever camp you are in, tomorrow's clash looks like becoming a defining moment in the history of the two clubs. And you can bet your Guinness that across the rugby heartland in France tomorrow, hundreds of thousands will be glued to their TV sets.