Despite enjoying a golden generation, Leinster have fallen short in their quest to add a fifth star to their jersey in recent years, with Ronan O'Gara aiming to plot their downfall for the second season running.
Sexton and Cian Healy are on the verge of becoming the tournament's most decorated players, as a Leinster win would see both veterans add a fifth medal to their collection.
Close to 60,000 supporters are expected at the Stade Velodrome, and with temperatures set to reach 29 degrees, Sexton is confident his side are ready for what will be a tough challenge.
“It’s important for us to win a fifth star because it puts us on a par with Toulouse, definitely, and we want to be recognised as one of the best teams in Europe,” the Leinster captain said.
“Obviously we are on four stars, but it hurt us a lot last year because we felt we had a chance to play them in the final and go for the fifth star against each other, and that wasn’t to be. So, yeah, it would be a big milestone for the club and it would be fantastic for us.
“You think when you get a bit older that you get a bit more relaxed but it’s been the opposite. When you know it’s your second last chance to win this, that puts a bit more pressure on but these things you learn how to deal with them.
“As a build-up to a big game it is the same excitement and nervousness. It’s tough at times. You torture yourself sometimes in the build-up but hopefully it will all be worth it once the game starts. Once it starts it feels like any other game.
“It’s tough every year. At the start when we won it we had a period of success, we won three in four (years), and you kind of think wow this is easy and then you go away and you don’t have it for so long and then you have so many tough days. You get so close at times. You talk about semi-finals recently, and finals, and it just proves how hard it is.”
Leinster's fitness will be put to the test in the searing heat, as Leo Cullen's men look to play their usual high-tempo game-plan and wear down La Rochelle.
The Leinster head coach is hopeful the heat won't negatively impact his side, with water breaks a possibility depending on the temperature come kick-off.
“It’s not too bad out there, I think if anything at 5.45, the pitch is in the shade,” Cullen said.
“When we turned up earlier, it was overcast, so there was no sun. When the sun is there, it feels a lot warmer for sure.
“Conditions will be great, a massive occasion, two great teams going at it, I don’t see it as a major issue. It’s warm, but yesterday when we left, it was lashing rain.
“I’d much rather have a bit more warmth in the air and I think all the lads prefer that as well. I think it should add to the occasion. The conditions will be excellent.”