London Irish withstood a furious late assault to hang on for a rare victory at Kingsholm which marks them out as major contenders in the Guinness Premiership play-off race.

Gloucester had a posse of England players - centres Mike Tindall and James Simpson-Daniel among them - eager to play their way into the starting line-up to face Wales at Twickenham.

But instead it was an Argentinian, number eight Juan Leguizamon, who claimed the game's only try, Australian Riki Flutey added a conversion and two penalties and veteran Mike Catt - no longer part of Andy Robinson's plans - comfortably outplayed both of his successors in midfield.

And while Ludovic Mercier's three penalties - two of them late in the second half - created some tension in the final moments, Irish hung on without too many alarms.

They will be the side least disrupted by international calls during the RBS 6 Nations and look ideally placed for a top-four finish which gives them a shot at the title and qualification for the Heineken Cup next season.

Irish had beefed up their pack for this game as they went in search of only a second league win at Kingsholm in 11 visits with Danie Coetzee returning at hooker, Nick Kennedy at lock and Olivier Magne moving to open-side flanker, while Samoan winger Sailosi Tagicikibau was on the bench for the first time.

The appearance of South African referee Jonathon Kaplan - warming up before taking charge of Scotland v France next weekend - should have produced a fluent game, particularly for the international hopefuls looking to impress watching England assistant coach Dave Alred.

Instead, both sides struggled for fluency in a first half punctuated by turnovers and unforced errors which was illuminated only briefly by lively breaks from James Simpson-Daniel and scrum-half Peter Richards.

Mercier and Flutey both missed early shots at goal before Gloucester's fly-half opened the scoring with a straightforward 19th-minute effort after Irish pulled down a scrum. Flutey replied two minutes later before the game opened up at last.

It took until five minutes before the interval for Irish to make a breakthrough, though, when Michael Horak's break from full-back set up the field position and the Exiles pack bundled Leguizamon over from close range with Flutey adding a difficult conversion.

The Argentinian had been the visitors' most effective ball carrier before staggering off following a blow to the head at the end of the half but they tightened their grip on the game when Flutey added another penalty two minutes after the break.

Trailing by 10 points encouraged Gloucester to chance their arm and the more adventurous approach suited them with Simpson-Daniel particularly dangerous when counter-attacking. One surge down the left got Mercier in range for a 30-metre penalty 20 minutes from time.

He added a third successful penalty 10 minutes from time but Irish ran the clock down with few alarms and Tindall was clobbered by eager defenders in the final move of the match.