Ronan O'Gara believes that Johnny Sexton has been fuelled by his Lions snub last year and has come back from that disappointment a better player.
Once rivals for the Ireland no 10 jersey, O'Gara and Sexton came to become firm friends when the former coached the latter in Paris.
Their paths diverge again in Marseille on Saturday when O'Gara, as La Rochelle's head coach, looks to stop the Leinster gameplan as put into effect by Sexton, who turns 37 in July but remains the province's driving force.
“He’s a great competitor and he loves rugby," said the Corkman of the Dubliner.
"People forget that, rugby is such a great game so you play it for as long as you can. If you’re good you keep going and he’s outstaying the rest in his position comfortably.
“But I think he’s also been fuelled...if you remember, there wasn’t much of a deal made by the fact he didn’t make the Lions tour.
"But that would have hurt him deeply.
"It’s another example of his excellent resilience and now he’s coming back.
"He’s made changes in the fact he’s always been a good passer of the ball but now he’s become a threat again, which he may have put on the back burner.
"But you saw against Toulouse, he has a very good running game, a good passing game, a good kicking game and he’s very good at seeing the opportunity before other people see it.
“That’s what a lot of great 10s do, he sees things quicker than other people - he’s able to manipulate his attackers and defenders into space because they’ve got great cohesion amongst them.”
O'Gara and Sexton also crossed swords at club level, the former winning two European crowns with his beloved Munster before the latter won four of his own.
"Obviously this final would have been different if it had bene against Munster, but at the same time it is a huge rival," said O'Gara.
"Leinster is a team I played against a lot, that I respect a lot and is very strong at the moment.
"If you spend your whole life in Cork, you love to beat them and it's the same for them when they play Munster.
"It's normal, there is a great rivalry. It's a bit like Paris (Saint Germain) and Marseille in football, a real rivalry.
"But all that is in the past these days. I'm coach of La Rochelle with a huge opportunity to win this final and that, I have to say, is very cool."
O'Gara is hoping to turn to sportswear from back home to boost La Rochelle's bid to conquer Europe for the first time.
Two of his key men, Will Skelton and Tawera Kerr-Barlow, were out of the European decider through injury.
However Skelton made a 15 minute cameo appearance in last weekend's victory over Stade Francais, a win that keeps La Rochelle's Top 14 hopes alive.
O'Gara is set to use the giant lock - who has destroyed Leinster in Europe before - against the Blues.
Scrum-half Kerr-Barlow has two broken bones in his hand. "I need to get some hurling advice and try and get one of those micro gloves," said O'Gara.
"You’ve got to explore every possibility.
"Depending on his pain threshold, depending on his grip of the ball and depending on...well, the legality of it I think is OK. People have played with those hurling gloves in the past.
“We just have to wait and see with that.”
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