Leinster stunned Toulouse in the Heineken Cup this afternoon, dumping the reigning champions on their backsides in their own backyard.

Outscoring the French aristocrats by four tries to two and amassing a tally of 41 points in Le Stadium will send shockwaves throughout European rugby as Leinster progress to the semi-finals where they will meet the winners of Munster and Perpignan.

Outmuscled up front, where the Toulouse pack consistently had the edge, Leinster never lost any of their ambition and from the minute Brian O'Driscoll put the visitors ten points clear with an expertly taken try in the 25th minute, Michael Cheika's side never trailed.

O'Driscoll's score was followed in the second half by scores from Cameron Jowett, Denis Hickie and Shane Horgan and while Yannick Nyanga and Yannick Jauzion crossed for Toulouse at the death, it was to prove mere consolation for the three-time winners.

With the threequarter lines consisting almost entirely of French or Irish rivals, the match was an opportunity for the nations to resume their Six Nations battles.

Jauzion's return from the broken toe which ruled him out of the entire Six Nations added spice to the contest - and the 27-year-old showed flashes of brilliance.

His performance was eclipsed by O'Driscoll's masterclass, with the Leinster captain scoring a magnificent first-half try.

But the most impressive display of all came from the only foreign player in the backs - Felipe Contepomi. The Argentina fly-half booted 21 points and was a hub of creativity, marshalling the visitors to good effect before fading in the last quarter.

Leinster will certainly enter the last four high in confidence, after bringing the tournament favourites to heel in such convincing fashion. The opening suggested a different outcome, however, with Toulouse close to their dazzling best.

Just four minutes into the game, beautiful footwork from Clement Poitrenaud opened a gap in Leinster's defence.

Jauzion continued the move, and an overlap was created on the left. But Vincent Clerc chose to go alone, and a glorious chance was wasted. Toulouse had won a penalty, however, which Elissalde rifled over - but Leinster responded with three points from Contepomi.

Clerc crossed in the 10th minute as the visitors were carved open by some devastatingly slick handling from the Frenchmen, but Jauzion's scoring pass was adjudged forward.

Elissalde and Contepomi exchanged penalties before Leinster took the lead for the first time, with their Pumas fly-half another three points.

Leinster's line-out was operating superbly. But they were finding it tough in the scrums where Toulouse's bigger pack had the edge, despite occasionally falling foul of referee Chris White's whistle.

The visitors, semi-finalists last year, were assured of quality possession from their line-out - and swift work at the set-piece in the 25th minute initiated their first try.

The ball was won quickly and fed to winger Shane Horgan, who burst through Toulouse's midfield before feeding Contepomi.

The Argentinian appeared to have run away from his support - but just as he was about to be tackled, he found O'Driscoll who had come racing through and the Ireland skipper evaded a tackle from Finau Maka before crossing under the posts.

Contepomi hit the routine conversion and the score stung Toulouse into action - but they only had an Elissalde penalty to show for a promising attack.

Girvan Dempsey found space down the left flank with a determined break, and Contepomi was once again involved before Leinster ran out of space.

Finau infringed, however, and Contepomi punished the error to give the Irish province a commanding 19-9 lead.

Panic broke out in the Toulouse ranks when Malcolm O'Kelly charged down a sloppy kick from Elissalde, but the veteran lock was unable to find his support with the line begging.

Elissalde slotted two penalties in the opening 10 minutes of the second half, and Toulouse began moving through the gears ominously.

A fabulous missed pass from Frederic Michalak released Cedric Heymans. But the France winger, who ran in two tries against Ireland in the Six Nations, chipped ahead into the arms of Dempsey.

Michalak kicked a drop goal to leave Toulouse trailing by just one point - but the fly-half then made a huge error which led to Leinster's second try.

His nonchalance when clearing in the 56th minute gave Jowitt time to break from the back of a scrum and smash him to the ground, before the Leinster flanker picked up the loose ball and strolled home.

Contepomi converted, and Elissalde replied with a penalty. But Leinster ran in their third try shortly afterwards, with Gordon D'Arcy and Hickie linking down the left.

D'Arcy fed back to Hickie, and the winger completed the 20-yard run-in despite a last-ditch tackle from Clerc which almost pulled him into touch.

Horgan showed strength to cross with 10 minutes to go - and when Contepomi converted and slotted another penalty Leinster had amassed an unassailable 38-21 lead.

Nyanga and Jauzion reduced the deficit with late tries - but by that point Leinster fans had already begun celebrating.

Scorers:

Toulouse
Tries: Yannick Nyanga (74), Yannick Jauzion (80)
Conversions: Jean-Baptiste Elissalde (74,80)
Penalty Goals: Jean-Baptiste Elissalde (7,12,31,43,48,58)
Drop Goal: Frederic Michalak (49)

Leinster
Tries: Brian O'Driscoll (26), Cameron Jowitt (54), Dennis Hickie (60), Shane Horgan (63)
Conversions: Felipe Contepomi (26,54,63)
Penalty Goals: Felipe Contepomi (9,16,19,36,67)