THERE wasn't a hole big enough for Leinster to dive into after another shocking Saturday in Stradey Park, though they managed to dig a pretty sizeable one for themselves with an extraordinary second half collapse. Even by Irish standards, this was classic house of cards' stuff.

After an entertaining, try laden first half, in which Leinster more than matched Llanelli in an absorbing nip and tuck 40 minutes, the ensuing disintegration was squirm inducing. So inept did Leinster's performance become that the ball became an embarrassment to them.

They didn't get much of the ball after the break, but when they did Leinster spilled it in contact, and even when there was no contact. Only once in the second period did they raise a gallop, Victor Costello breaking out of his own half and his own inertia to thunder through three tackles in a 40 yard drive. But Stephen Rooney's transfer to Malcolm O'Kelly was knocked on in the tackle.

Several moments summed it up, such as the laboured 75th minute blindside move between Ala in Roland and his back row at 17-26 in arrears. They lost control of the ball, regained it, turned it over again, looked utterly bunched, conceded a penalty and an extra 10 metres for dissent, thereby enabling Frano Botica to land his seventh kick out of eight.

At times, the Welsh crowd, demonstrating a typically smug superiority complex, laughed in derision. Long before the end you wanted it to end.

Leinster didn't help themselves by naively kicking straight to touch, whereupon, Llanelli's 20 year old lock Vernan Cooper served it up on a plate for Rupert Moon.

Coach Ciaran Callan candidly acknowledged Leinster's capitulation. "I was reasonably happy with the first half. We were playing the game at a reasonable pace. We were punching holes. We looked like a side that would win it at half time and the whole game seemed to go to pieces in the second half. We had no ball.

"Any ball we got we turned over. We either gave silly penalties away, or we kicked badly, or we lost it in contact; and our hands went in the back line."

Given a choice for explaining this the infusion of the London Irish rebels and thus an unsettled side, sheer fitness levels, or a mental collapse, or something else - Callan opted for the mental option. In defence of this theory, manager Jim Glennon pointed to the rollercoaster effect a Welsh side such as Llanelli achieves when establishing some momentum, and the ensuing desperation which crept into Leinster's play on the isolated occasions they had crumbs of possession. "They didn't have it within them to lift the men Ia, edge. A certain lethargy crept in.

But perhaps Callan and Glennon find it too unpalatable to accept that the age old flaw in Irish fitness levels manifested itself again.

Like Callan, Llanelli coach Gareth Jenkins felt that Leinster were the superior side in the second quarter of the game and looked capable of winning. "Yet we believed that with 20 minutes to go they [Leinster] had gone, fitness wise." It certainly looked that way.

Equally damning was the verdict of Llanelli captain Robin McBryde. "If we're going to progress against possibly bigger and better teams, then we'll have to tighten up in the set pieces and the loose. There were too many mistakes. We've also got to hit the rucks much harder." Indeed, in the first half, Leinster detected a soft underbelly in the home pack.

Botica, playing only his second game for his new club, was man of the match by a street, controlling proceedings, kicking unerringly, providing a running threat of his own and creating space for those outside him. With Mike Voyle to return up front, and with a trio of internationals, Wayne Proctor, Ieuan Evans and Nigel Davies, to come back into the back line, Llanelli will improve.

Despite a poor crowd of about 2-3,000, Jenkins maintained this competition was "huge" for his club. "These are the games that are going to finance the step up to professionalism. If they don't become lucrative, then we've all got problems."

The same must apply for Irish rugby, though ominously the European Cup prognosis does not look encouraging this season. So where now. Leinster? Knock, joked Glennon, who accepted that this was Leinster's pivotal game of the season, much as the opening away win in Milan had been last season. Now they are on the back foot.

There is an argument that Leinster are seeking to play a brand of 5 man, continuity rugby that is beyond them, as much because of personnel at their disposal (two blind side flankers in the backrow) as anything to do with fitness or ability. Yet resorting to a mauling style must surely be a forlorn, backward exercise in the modern game.

Their shell shocked squad will regroup for training on Monday, after the selectors revise their options and pick a team that may not be released until Tuesday, prior to Wednesday's home joust with Leicester. A good few changes seem inevitable. Uppermost among them is likely to be the return of Dean Oswald who would make the biggest difference to this team.

Either way. Leinster have their backs to the wall now, which takes us to another Irish rugby custom. It may, conceivably, bring out the best in them.