True, it wasn't the most fluid or potent of Munster performances, but in a competition where away wins are like gold dust this was a classic smash-and-grab away conquest at the Stoop.

For all Munster's successes at home and abroad, as Declan Kidney pointed out afterwards this was only their second in England and against a side who had won 15 of their previous European games and domestic cup ties. It was also a very Munster coup.

Home hopes having been stirred by David Beckham's last-gasp dramatics moments before, the Stoop was still reverberating to the hum of sporting patriotism when Ronan O'Gara kicked off. Munster are one of the biggest draws in Europe now and the capacity 9,000 attendance also made for as big a corporate/sponsor's day out as the competition will witness in the pool stages.

Hence, initial attempts at the Fields of Athenry from the Red Army (the official 1,000 sold via the Munster branch looked to have been doubled by expatriates) were drowned out with the help of one of those nauseatingly over-the-top p.a. announcers, which are now de rigueur.

But, predictably, by the end only the visitors were singing, a bouncier, clap-along version of the Munster anthem celebrating a win which prompted a grateful lap of honour from Mick Galwey and co.

Harlequins had taken the game to Munster auspiciously and trailed only 13-5 at the break, with the wind behind them to look forward to in the second-half, yet thereafter they never really looked like winning as Munster ensnared them in their vice-like grip, suffocating the life out of the home team with their smothering defence.

Admittedly, it was one of those days when Munster had to gradually crank things up and grind out a win.

Somewhat as expected, John Kingston's team were well organised defensively and also ate into the Munster line-out in the first-half especially.

Sluggish starts are not unusual for Munster and in the first five minutes alone here Anthony Foley knocked on, Ronan O'Gara (again targeted defensively) missed a tackle on Will Greenwood, Mike Mullins then knocked on and so too did Jim Williams.

Harlequins made four clean incisions and the opening try by the lively Dan Luger highlighted the stand-offish nature of Munster's first-half defence. But they limited the damage of that first quarter and it was probably as well they had first use of the wind. This enabled O'Gara, whose line-kicking was masterful, and the big boot of Jeremy Staunton to play for territory, the out-half punishing needless indiscretions at the breakdown by the prominent Tu Tamarua and Keith Wood to edge Munster in front.

Staunton's 75 metre Exocet was the platform for the crucial end-of-half try, which had a hint of Keystone Cops about it as O'Gara pounced on a ricocheted fly hack from Peter Stringer which Mark Mapletoft failed to gather.

Turning the screw via O'Gara's masterful line-kicking, mauling the Quins pack virtually off the park as the sheer strength and will of the Munster pack came into its own, Munster upped the tempo sufficiently for two drop goals off trademark spells of continuity before Jason Holland - impressive in everything he did - pounced for an 80th-minute try.

As much as ever before the thought occurred that Munster must be an utter pain in the ass to play against, prompting Kingston to again describe them as Ireland's version of Leicester. "Munster played very-low-error rugby," said a palpably frustrated Wood, who'd been quiet enough and seemed to be mostly used as a decoy. "They had great defence, time after time, and then pounced on our mistakes. It's clinical rugby, which Munster is fully capable of doing."

Yet in a wider scheme of things, this was a hugely important psychological step forward for Munster. "We've played in England before and it hasn't worked out for us," said Kidney, in reference to the sodden Twickenham final of the year before last when the Northampton pack bullied them a little in the set-pieces, and also to that saturated Saturday in the Rec when they were swamped up front in Bath, not to mention the sodden semi-final surface in Lille.

Thus, this will constitute a particularly satisfying win for Munster, and what will have satisfied them most were the scrums, where Peter Clohessy had a particularly productive day against Adrian Olver, and their mauling game. The crunch period was the third quarter when Munster turned around to face the wind, and stymied Harlequins' attempted drives before launching a huge one of their own off O'Driscoll's take in the prelude to O'Gara's drop goal.

Kidney, keeping O'Gara's second successive man-of-the-match award in as much perspective as his much criticised Murrayfield display, commented: "He's a very good team player. Outhalves get unnecessary glory at times and some unnecessary criticism. Today he was no better and no worse than most days."

From an Irish perspective, aside from the close-in strength of Galwey, Hayes and Clohessy, Anthony Foley again cast away his rare off-day against Scotland by tackling big in a typically industrious performance, Peter Stringer's service was excellent and Mike Mullins was his lively self.

Galwey confirmed that there had been a fair amount of banter and "Limerick stuff" involving Wood and his erstwhile Munster team-mates, the reunion of six of last summer's Lions also prompting regular dialogue, especially between O'Gara and Greenwood.

The Stoop, oft derided as snooty, could hardly have been more hospitable. "See you in January," said Kingston to a departing Kidney. "Unfortunately," quipped Kidney.

"Good luck to you," said Kingston magnanimously. "If we can't get through, I hope you do."

Scoring sequence: 15 mins: Luger try 5-0; 18: O'Gara pen 5-3; 29: O'Gara pen 5-6; 40: O'Gara try and con 5-13 (half-time 5-13); 46: O'Gara drop goal 5-16; 61: Burke pen 8-16; 73: Holland drop goal 8-19; 80: Holland try 8-24.

HARLEQUINS: M Mapletoft; M Moore, W Greenwood, N Greenstock, D Luger; P Burke, S Bemand; J Leonard, K Wood, A Olver, G Morgan, S White-Cooper, R Winters, T Diprose, T Tamarua. Replacements: P Sanderson for Winters (60 mins), A Codling for White-Cooper (75 mins), N Burrows for Greenstock (77 mins).

MUNSTER: J Staunton; M Mullins, J Holland, A Horgan, R O'Gara; P Stringer; P Clohessy; F Sheahan, J Hayes, M Galwey, M O'Driscoll, J Williams, A Foley, D Wallace. Replacements: P O'Connell for O'Driscoll (51 mins), M Horan for Clohessy, D O'Callaghan f or Galwey (both 81 mins), C McMahon for Wallace (84 mins).

Referee: N Whitehouse (Wales).