Bryan Habana's extra-time try ensured Toulon eventually defeated Leinster 25-20 following a gripping European Champions Cup semi-final in Marseille on Sunday.
Habana's opportunistic score was the key moment according to Leinster Head Coach Matt O'Connor. "Habana's intercept was the turning point - he is world-class - but the positive for us was the effort. It was second to none.
"The effort the lads put in was fantastic and we are obviously incredibly disappointed to come second.
"A lot of people had written us off coming into this game, but we will back ourselves to go anywhere and beat anybody."
Leinster captain Jamie Heaslip added: "It felt like a boxing match out there. There was nothing between the sides.
"We probably left opportunities out there in the first 40 minutes and they had a purple patch in the first 20 minutes of the second half, but we stood our ground.
"We always have an inner belief that if each player does their job, we are a good team and we can create situations to get some points."
Toulon coach Bernard Laporte said: "I feel very relieved indeed. It was not easy, and we were a bit vulnerable.
"We made a lot of mistakes - on a better day we might have won the game by a bigger score, but we showed tremendous spirit.
"There are not many games at this level that you play during a season and it is the team that makes fewest mistakes that mostly comes out on top."