The last of the Parisian smog lifted yesterday, making it a perfect day in more ways than one. Departing for a flight home, the Irish rugby team breathed the city’s clear air as Six Nations champions. Behind them, lingering supporters basked in sunshine and reflected glory.

Rugby aside, the weekend may have been a triumph for Tourism Ireland. As Paris made its entire public transport system free from Friday until Sunday, to cut car pollution, vast numbers of people took to the Metro, which even on Saturday afternoon was like the Tokyo subway at rush hour.

Irish pubs
Once underground, they were exposed to ubiquitous billboard posters inviting them to "Vibrez au rhythme de l'Irlande", accompanied by pictures of an unspoiled and unpopulated Wild Atlantic Way. Given the local overcrowding, not to mention the air conditions, it looked a very attractive alternative.

Not that anyone had to leave Paris to vibrate to the rhythm of Ireland this weekend. It was an unavoidable fate in and around the city’s multiple Irish pubs, and many non-Irish ones, on Saturday night.

In the Green Linnet bar (so-called after a poetic code-name for Napoleon during the Franco-Irish alliances of two centuries ago), the madness reached a height of sorts with a mass rendition of the Pogues' Fairytale of New York . It was a song about the wrong city, in the wrong season, and its mood was all wrong too.

But it concerned a fairytale, and that was relevance enough. Irish Six Nations titles of any kind are rare. Titles – or even games – won in Paris border on miraculous.

And in this case, there was the added marvel of what it meant to the legend of one Irish player in particular.

Saturday’s game wasn’t all about Brian O’Driscoll. But in this most symmetrical of cities, the way he had just book-ended his career was a thing of architectural beauty. It finished for him in Paris as it began, with a two-point win. He didn’t score the hat-trick of tries this time – Johnny Sexton and Andrew Trimble had to do that for him.

But the overall effect was near enough perfection. Maybe the French should erect matching statues of him on either side of the Pont Neuf to mark his achievements here.

If only the game itself had been as enjoyable as the celebrations that followed. There was a heady moment midway through the second half, with Ireland nine points up, the home fans silent, and the Fields of Athenry ringing around the Stade de France, when it looked as if, for once, supporters' fingernails would be spared.

The more optimistic among us thought that, along with the public transport system, the home team's defence was about to be thrown open to visitors, and that we might have the freedom of the pitch for the last quarter. Of course, that didn't happen.

Battle to the death

We should have known beforehand, when the band of the French Foreign Legion played the anthems, that the game would be a battle to the death. So it proved, all the excruciating way to the final whistle.

In the immediate aftermath, the mood in the stands was as much relief as joy, with many green-shirted supporters having to unwrench their guts before getting into party mode. They made up for it later, riding the free trains back into town on a mission to liberate the city of its beer supplies.

A weekend in which the Irish owned Paris had begun rather more sedately. Seizing the moral high ground – aka the Basilica of Sacré Coeur, which overlooks the city from the hill of Montmartre – several hundred of the visitors attended the city’s official St Patrick’s Day Mass on Saturday morning, two days early.

Irish ambassador Rory Montgomery and Tánaiste Eamon Gilmore were among the congregation, which then repaired to the nearby Corcoran’s Pub, where they were treated to – yes – tea.

The premature Mass was not an attempt to influence the match result, apparently.

And in any case, even some religious Irish supporters were having an each-way bet on the outcome, praying to St Patrick while wearing shirts with the slogan "In Bod We Trust" on the back.

Moulin Vert

But whether the 5th-century miracle worker was directing events or not, he might have taken a dim view of the rest of the weekend’s celebrations.

The descent from moral altitude was still under way last night when, just down the hill from Montmartre, the Moulin Rouge became the Moulin Vert in time for March 17th, the performers of the Can-Can being supplemented for the occasion by members of Riverdance .