IT IS 8.15pm, Cardiff, Saturday. St Mary Street is still pedestrianised, heaving, part bacchanalian, part apocalyptic, those who aren’t drunk are in the queues so they can soon become so. Something is wrong in the state of rugby. It just wasn’t supposed to happen like this any more.

Irishmen noticed it too, and that was even before kick-off. A carnival city swarming with red and green and brimming with mirth. On the bus ride through the parting crowds, David Humphreys, who has been in the Ireland team for ten years, nudged Brian O’Driscoll, his captain, and told him he had never known an atmosphere like it. They have staged a rugby World Cup here at the Millennium Stadium but it felt nothing like this.

Professionalism, the maximising of resources, the perfection of sports science all appeared to have legislated against occasions like this, which is why it felt so unique.

“Romance” was a word dragged out and pinned to the newspapers last week, but only because the forward march of the game appeared to have done for it. In a decade of professional rugby, the strong have simply got stronger, the playing field seemingly tilted ever further in their favour with the likes of Wales in danger of slipping off for good.

Goodness knows how much we had heard too of that great Wales side of 1978, but there is a reason for this beyond mere nostalgia. Sober Welshman, and there may be a few of them again by now, would not have predicted with any certainty that they would see another grand slam in their lifetime.

And so to Shane Williams in the last ten minutes of the game, with Ireland attacking relentlessly and the red dragonhood in the stands starting to think: Surely they can’t lose it from here. Even now Williams elected to run, to twist and turn his way out of trouble rather than put boot to ball. “The big thing is we went out to play all season without fear,” Mike Ruddock, the Wales coach, said afterwards. “It’s not a game of can ’t, it’s a game of can.”

But it is a lot simpler to play without fear when you do not have so much so lose. Wales had a grand slam to win or lose here, the first in 27 years as everyone knew all too well, so a tightening and edge to their game would have been understandable, predictable even. Think back 16 months and a day to England’s World Cup, to Sir Clive Woodward’s team that played tighter and tighter as the trophy got closer. They called it pragmatism and pragmatism worked.

Wales, however, do not know another way, certainly no other way had ever seemed to work. This is the team with the players famously described as “diddymen”; they certainly do not have the physicality to win it tight.

So they stayed true to Ruddock’s word to the last; even when Ireland were slashing merrily through the points deficit, Williams stuck with the team ethic.

They celebrated afterwards like England did 16 months ago, but there was a sober note to their reflections. The tide of rugby union in the professional era has swept in the bigger nations even more strongly than before and so Wales’s triumph this season has an air about it of a boat surging pluckily against the current but one that will soon be swamped and sunk again. It errs against recent history, it has a one-off look about it. But none of these Welshmen would be happy with that.

Martyn Williams talked of “being a great side”, of the need “to win more things”. “We’ve got to keep working,” he said. “We’re far from the finished article”.

“We’re still struggling a bit at the breakdown,” Tom Shanklin said. And that was exactly the sort of thing an Englishman under Woodward would have said, because, even in their moments of glory, they were never entirely happy either.

“There’s more to come from this team,” Ruddock said, his justification the fact that their average age is in the mid- twenties. Of Saturday’s intended starting XV, only Brent Cockbain and Mefin Davies have hit 30. Which is why Gavin Henson was happy to muse so positively on the future. “Things look really bright for the 2007 World Cup,” he said. “It’s a long way off but that’s what we’re building for.”

Which is quite some statement. What Wales have demonstrated is that you do not have to be a superpower in world rugby and you do not have to be a team of behemoths.

Turning the rugby world on its head for a matter of two months has been one truly astonishing achievement, to do it playing in such style is another. The challenge they have set themselves now is to defy the history and logic of their sport on a permanent basis.

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