Toulouse won a record-extending sixth European Champions Cup when a Matthis Lebel try helped them beat Leinster 31-22 after extra time on Saturday in a fittingly seismic clash between the tournament's most successful teams.
The game was locked at 15-15 after 80 minutes before Label broke it open with the first try of the match and Thomas Ramos kicking the French side clear.
Leinster fought back to within three points after a Josh van der Flier try but two quick penalties by Ramos condemned the Irish province to a third successive final defeat.
"It is awesome to be able to win with this team," said Toulouse's man of the match Antoine Dupont. "We really wanted to win the sixth star after losing to Leinster over the last two years [in the semifinals]."
The match between two of the best attacking teams in the world, both appearing in the final for the eighth time, proved to be more of an arm wrestle as Toulouse led with two penalties from Blair Kinghorn.
Leinster got a foothold but Toulouse's ferocious defence -- typified by a superb try-saving tackle by Kinghorn on Dan Sheehan - and aggressive work at the breakdown restricted them to a Ross Byrne penalty in the first 38 minutes
Toulouse had averaged 6.6 tries and over 44 points per game in the competition this season but were happy to opt for another Kinghorn shot from the tee, before Byrne replied to make it 9-6 at halftime.
If it was not the feast of free-flowing rugby many had hoped for, it was still a monumentally intense clash between the two heavyweights of European club rugby, meeting at the ultimate stage for the first time.
In defeats by La Rochelle in the last two finals Leinster had roared into early leads but it was a different narrative on Saturday as, having absorbed huge first-half pressure, they drew level at 9-9 with another Byrne penalty.
Two more penalties made it 12-12 before Toulouse thought they had scored a spectacular try when Lebel caught Romain Ntamack's crossfield kick but Jordan Larmour had done just enough to force his foot into touch and the TMO ruled it out.
The French side were ahead soon, however, through a penalty from replacement Ramos, but with three minutes remaining Leinster earned a scrum penalty that replacement flyhalf Ciaran Frawley slotted to make it 15-15.
His attempted drop goal to win it floated wide and the final went to extra time for the third time.
Inspired by the increasingly influential Dupont, Toulouse continued to drive forward and Leinster cracked when Santiago Chocobares burst clear and allowed Lebel to turn on the after-burners and score the opening try.
Ramos converted and added a penalty to open a 10-point lead but the game swung back Leinster's way when Australian lock Richie Arnold was red-carded for a dangerous hit.
Leinster took immediate advantage with a pushover try by Van der Flier that needed a lengthy TMO intervention. Frawley converted to make it 25-22 at halftime of the extra period.
Toulouse then claimed a decisive stranglehold with two Ramos penalties to take the wind out of Leinster's sails and make it a hat-trick of heart breaks.
"We're pretty devastated. We poured a huge amount into this game," Leinster head coach Leo Cullen said.
"It was a game that was about taking opportunities, we had plenty of opportunities, some we couldn't quite nail. It's important we show character as a group now. Toulouse showed the champion qualities they've got."