London Irish's Heineken Cup hopes nosedived at Stade Ernest Wallon - but they gave three-time European champions Toulouse a determined run for their money.

The Exiles' second successive Pool Five defeat means their quarter-final chances are hanging by a thread, and even victories in all four remaining games against Ulster (twice), Llanelli Scarlets and Toulouse probably will not be enough.

Irish though, stuck to their task, piling pressure on Toulouse during the closing 10 minutes in pursuit of a losing bonus point.

Ultimately, they had to settle for tries by full-back Delon Armitage and lock Kieran Roche, while Armitage slotted a conversion after he took over kicking duties from Barry Everitt, who earlier landed a penalty and conversion.

Toulouse led 27-10 early in the second period following tries from Yannick Jauzion, Xavier Garbajosa and Florin Fritz, but it was not until injury time that a bonus point score arrived when substitute forward Jean-Francois Montauriol ploughed over.

Scrum-half Jean-Baptiste Elissalde chipped in with 15 points from the boot and substitute Valentin Courrent kicked the final conversion, yet the final margin was harsh on Irish.

The Exiles were dealt a late injury blow when fly-half Riki Flutey was forced to withdraw after suffering a groin strain during kicking practice last night that could sideline him for a month, so Everitt took over and Richie Rees received a late bench call-up.

Toulouse, bristling following a 30-3 defeat against Ulster last weekend and subsequent citing of three players for alleged foul play, switched France international centre Jauzion to fly-half and teamed Gareth Thomas with Fritz in midfield as coach Guy Noves rang the changes.

Conditions were ideal for a running spectacle as the temperature topped 25 degrees, and Irish rocked Toulouse with a try inside two minutes.

Wing Topsy Ojo skipped inside some weak Toulouse tackling, and before the home side could regroup Roche delivered a scoring pass to Armitage, whose angled run allowed Everitt a simple conversion attempt.

Irish were not remotely fazed at the task in front of them, and even though Toulouse struck with a brilliant try just three minutes after Elissalde slotted a penalty, they continued to place a healthy emphasis on attack.

Toulouse's opening touchdown came after wing Cedric Heymans stepped out of Ojo's attempted tackle, and despite having little room to work in, slick passing from Heymans and Fritz sent Jauzion over.

It was a score breathtaking in its execution, underlining how Toulouse have few peers when it comes to attacking flair and invention.

Toulouse almost eclipsed Jauzion's effort just 10 minutes later by attacking from deep inside their own 22 after Elissalde took a quick lineout throw. Six passes on, and they were within sight of the Irish line before the Exiles infringed and Elissalde made it 13-7.

Toulouse now had the bit between their teeth, and more rapid approach work with Jauzion at its heart created enough space for Garbajosa to sprint over unopposed.

Elissalde converted, and although Everitt restored a degree of order by landing a penalty, Irish were increasingly playing catch-up.

But they fought on bravely, if somewhat breathlessly, and prevented Toulouse from causing further damage before referee Nigel Owens ended a frantic first half.

Irish's problems mounted though, within three minutes of the restart. Having substituted Everitt with Argentinian centre Gonzalo Tiesi, skipper Mike Catt limped off, meaning scrum-half Paul Hodgson took over number 10 duties as Rees replaced Catt.

It all amounted to fairly major disruption for the visitors, and Toulouse moved 17 points clear when a magnificent Thomas off-load in contact gave Fritz a clear run to the line.

Thomas required treatment after taking a blow on the head when he was tackled, but he quickly resumed duty as Toulouse went flat out for a bonus point.

The energy-sapping weather seriously tested Irish's fitness levels, especially with Toulouse continuing to attack from deep, but the Exiles' brave performance saw them grab a second try through the hard-working Roche that Armitage converted.

Toulouse, in contrast, suddenly switched off and were forced into a long period of defending as Heymans was sin-binned for killing possession.

But Elissalde's third successful penalty and Montauriol's close-range effort calmed their nerves, sealing an anticipated victory that put them back on course in Europe this season after the Belfast drubbing.