As Jonathan Sexton walked out of the RDS for the last time as a Leinster player on Saturday night, a supporter shouted: “See you in two years, Johnny.”

It's not that simple. There are other factors at work. "It's a two-way process," Sexton said. "The good thing about Leinster over the last few years is we have replaced everyone that's left. Rocky Elsom left, Kevin McLaughlin and Seán O'Brien came in. Brad Thorn left, Devin Toner has filled his boots.

“I’m sure guys will come in and fill the spot I’ve had for a few years.

“But it’s a two-way thing. They’ll have to want me back. Obviously, this is a very special place, I love this place.”

And then he said it: "I'm sure if I was dealing with them [Leinster] alone, I think they rate me, so from this point or that point of view . . . Maybe I'll be back some day, maybe not; maybe Leinster will go on ahead and win another couple of Heineken Cup trophies and a couple of Rabos, you just don't know."

How on earth did the IRFU lose such a prized asset, who so clearly wanted to stay? The full answer to that question will only come in time but Sexton didn’t become the driving force in this dynasty by mincing his words: had he just been dealing with Leinster, next season’s Paris adventure, alongside Ronan O’Gara, Dan Lydiate, Jamie Roberts et al, wouldn’t be happening.

He was very clear about that when speaking to the media on Saturday night after conducting the clinical dismissal of Ulster in the Pro 12 final.

It wasn’t Leinster’s decision to let him go either. It was made elsewhere. By others. There are two sides to every story and it’s for Sexton to tell.

Just not yet.

So, the 27-year-old’s lifelong association with the franchise ended as he twirled Brian O’Driscoll over his head after the great centre booted the ball into touch. It was their last moment on a rugby field in the blue jersey. From now on, red and green only.

When his agent Fintan Drury and Racing Metro 92 president Jacky Lorenzetti hammered out a two-year deal in January, it meant Sexton and O'Driscoll's career paths would take markedly different routes. O'Driscoll never left Dublin, Sexton feels he has no choice but to go.

Seven other players will leave this summer – Heinke van der Merwe, Tom Sexton, Isa Nacewa, Jamie Hagan, Andrew Conway, Fionn Carr and Damien Browne – and Sexton spoke in the dressing room afterwards about his exit.

“It was tough to talk to the group. I think they know how I feel about the whole thing. I said I never thought it was going to happen like this. I’m going to miss them. This team has been everything to me for the last seven years, maybe too much at times.

"Some of them are probably glad to see the back of me. They'll be quieter training sessions next year.

Great adventure
"I've got a great adventure ahead of me and I'm going to give it all for my new team. I don't want to insult [Racing] but I also want to let everyone know what Leinster meant to me for the last few years."

Sexton was assured by Lorenzetti that his international career will not be hindered by the Paris club.

After three years, six finals and four trophies, he's glad to continue his working relationship with Joe Schmidt. It all began with Schmidt trying to recruit Isa Nacewa to Clermont Auvergne only for his fellow Aucklander to flip the conversation on its head.

Then, in early 2010, Sexton and Leo Cullen were the emissaries sent to meet Schmidt.

“I remember leaving the meeting and saying to Leo, ‘This guy’s obviously a brilliant coach but you reckon he is harsh enough to be a head coach, he seems so nice?’ “Leo just said: ‘He was a principal of Auckland Boys School when he was 26 or 27 so I think he’ll be alright.’ I just thought we needed a good coach anyway. He turned up...”

Schmidt’s Monday morning sessions, regardless of the weekend’s result, are famously cutting affairs. “ He was harsh enough anyway. But he is an outstanding coach, an outstanding person. Everyone wants to play for him. I think that is so special in a coach, to be a good technical coach and to have everyone play for you as well. A mixture of the best, I think.”

The end of a blue dynasty, the beginning of a new adventure.