Toulouse called on their Heineken Cup experience to power into their fifth final and halt London Irish's European journey at Twickenham.

Irish capitalised on appalling defending from France full-back Cedric Heymans to plunder tries through Topsy Ojo and Sailosi Tagicakibau in each half - but it was was enough.

Luckily for Heymans, Toulouse showed greater efficiency in attack with Manu Ahotaeiloa and William Servat crossing in the space of four minutes shortly before the interval.

The French giants, missing a host of stars including Clement Poitrenaud and Vincent Clerc, would have made life easier had skipper Fabien Pelous not butchered two fine chances.

But the three-times Heineken Cup winners, perennial fixtures in the knockout stages, possessed too much nous for Irish once they had edged ahead.

Leading their assault was France half-back Jean-Baptiste Elissalde, who kicked 11 points and expertly marshalled his weakened side.

They will now meet either Saracens or Munster, who play at the Ricoh Arena in Coventry on Sunday, in the final at the Millennium Stadium next month.

Irish, who were missing Mike Catt to a hamstring and calf injury, had surpassed all expectations to reach the last four but came up short against their more streetwise opponents.

They subjected Toulouse to a nerve-shredding finish as they went in search of the converted try that would snatch victory, but the French club held firm.

Ojo finished with the man-of-the-match award and the flying winger was only denied an early try when opposite number Yves Donguy dealt with Peter Hewat's crafty chip in the nick of time.

The roles were reversed in the ninth minute when Donguy was threatening to scoop up a loose ball in the 22 but Ojo came to the rescue.

Elissalde, playing at fly-half with former New Zealand international Byron Kelleher starting in the number-nine jersey, and Hewat swapped penalties but Toulouse were in control up front.

A moment of brilliance from Ojo sent Irish surging ahead, however, with the lightning-quick right winger ripping through the Toulouse defence from a standing start.

The Exiles did well to keep the ball alive and Ojo scented blood, beating Elissalde on the outside and then arching past a feeble last-ditch tackle from full-back Heymans.

Hewat converted to send Irish 10-3 ahead but they were at panic stations on the half-hour mark when Fabien Pelous marauded into space.

The Toulouse skipper and former France lock had time to make the scoring pass but delivered it to the feet of a frustrated Donguy.

Better handling meant a second chance was not butchered shortly after as a series of bullet passes sent centre Ahotaeiloa diving over.

Irish cracked again in the 38th minute when France hooker Servat completed a line-out catch and drive and this time Elissalde made the conversion.

Toulouse's vast Heineken Cup experience meant they were in the box seat heading into the second half but they were undone by another blunder from Heymans.

Line-out ball was quickly fed to Tagicakibau who was stationed on the touchline and appeared to have no escape route.

But he did not reckon with Heymans' pitiful challenge that slid down his legs and having beaten a similarly poor effort from Maxime Medard, he raced 30 metres to score.

Toulouse responded with two Elissalde penalties as the match once again began to slip away from the Exiles and Pelous should have sent Shaun Sowerby in for a third try.

Ojo exposed Yannick Jauzion's lack of pace with a stunning break but he just failed to get the scoring pass off to Tagicakibau on his shoulder.

Irish continued to search for the converted try they needed to win but Toulouse held out in a nail-biting finish.