RONAN O'Gara was delighted to lift the trophy as he became only the third person to win the Heineken Champions Cup as a player and head coach after his La Rochelle side beat Leinster 24-21 at Stade Velodrome, in Marseille.
O'Gara joined Leinster counterpart Leo Cullen and Toulouse's Ugo Mola as scrum-half Arthur Retiere squirmed his way over from a ruck on the Leinster line to score his side's winner with a mere 17 seconds left on the clock.
Four-time champions Leinster came into the game as firm favourites and looked set to join Toulouse on a record five wins after Johnny Sexton kicked six penalties and his replacement Ross Byrne added a seventh to put their side 21-17 ahead with 15 minutes to go.
But La Rochelle's third try in the final minute of the game from Retiere earned them a first major trophy to make up for losing in the European Challenge Cup final in 2019 and last season's Champions Cup final.
"We made a plan and our want was huge. There was nothing in it, but the key was taking away Leinster's space and time," said O'Gara, who won the title as a player with Munster in 2006 and 2008.
"I told Arthur I hoped to give him 30 minutes to allow him to go on and win the game.
"There was a lot of finishing in his try, because we had hammered away for about 40 phases before that. There was a lot of discipline in that and it was a super finish.
"There are certain players in football, like Ruud Van Nistlerooy, who you know are going to get goals and Arthur Retiere is a brilliant rugby player, but he is an average number nine and an average winger. He is a brilliant player without a position.
"Leinster are usually out of sight in the first half so at half-time - when we were five points behind - I asked the players 'what's the problem'? The data shows we score 60 per cent of our points in the last quarter.
"It was such a tense game and it all feels a little bit surreal that we will wake up in the morning as European champions."
Man of the Match Will Skelton picked up his second winner's medal having been in the Saracens side that beat Leinster in the 2019 final in Newcastle.
He had spent four weeks in rehab getting over a calf injury to be fit for the final and came into the game on the back of 15 minutes of rugby in a month.
"This means everything to this club, the players and to me. We are only a small town, we aren't supposed to be playing in these big games," said Skelton.
"It hurt a lot last year when we were beaten by Toulouse but sometimes you have to lose before you can go on to win the big one.
"We showed a lot of character and the way we won it shows how much we care for this club, the town and each other."
Leinster skipper Johnny Sexton had hoped to lead his side to a record-equalling fifth title in his sixth final, but had to settle for a second runners-up medal.
"I am pretty lost for words. We didn't play our best game and we weren't allowed to play our best," admitted Sexton.
"We will have to take a look at that before we can point any fingers. There were a few things at the end of the game that I don't understand.
"But we didn't clear our lines and we paid the price. This is an incredibly hard competition to win and when you get to the final, it is the hardest game of the season.
"We had some chances that we didn't take and we kept the scoreboard ticking over. It was just devastating to lose it in the way we did at the end."