He didn't fully realise it at the time but Johnny Sexton was a changed man upon his return from France.

Back in 2013, the Ireland out-half made the shock decision to up sticks and left Leinster to savour life in the Top14 with Racing 92.

The then-27-year-old had helped deliver Leinster to three Heineken Champions Cup titles so the switch to Paris surprised the rugby world.

The French connection comes up annually ahead of Ireland-France clashes and Sexton was in a reflective mood at yesterday’s press conference and was asked about how the experience helped him to improve as a player.

What exactly did he learn to do and even more interestingly, what did he learn not to do?

Sexton with head coach Laurent Labit

"I was signed and I had some meetings with the president [Jacky Lorenzetti], and he said: 'I want you to change the culture and I want you to bring a winning mentality'," said Sexton, who will win his 111th cap on Saturday.

"And I went in all guns blazing and figured out that there wasn’t that many people there to do the same thing, whereas I should have gone back and tried to make friends first and build relationships, and it stood to me now.

"Like, when there are new guys coming into the environment here you need to build relationships with people and Andy [Farrell] is big on that.

"So it was a good eye-opener for me, and at least then when you’re coming from a good place in terms of standards, at least you’ve got a basis to work off with someone."

Sexton’s two-year stint was hampered by injury and didn’t work out as planned; meanwhile Leinster also struggled, relatively, without their main man and a return transfer was arranged.

But lessons were learned, even if it wasn’t so obvious back then.

He added: "I didn’t think at the time but I remember meeting up with [then Leinster boss] Matt O’Connor for a coffee just before I came back and he thought it did benefit my game because I had to figure out how to try and win games differently with a team that probably wasn’t as good at playing rugby as Leinster used to play or as organised, and I had to figure out a way.

"I think in hindsight he was probably right. Matt was a very intelligent rugby guy and yes, I probably did learn a lot.

"I learned a lot culturally, like what not to do. I learned a lot about myself in terms of leadership.

"So yeah, lots of lessons in my time there."

Sexton’s history with the country means the build-up to this fixture is always special for him.

"From my point of view, I had a great couple of years there," he said about the cultural experience and alluded to the various comments about the state of his health that usually emanate from somewhere in France.

"I've got some great friends there, my son was born there so for me it's fond memories.

"It's these weeks that [barbs] go the other way from the other side. Hopefully, it won't this week but we'll wait and see.

"But no, it hasn't soured it. I have great memories of living there and loved the country. I always think it's a great challenge playing against them.

"I went in all guns blazing and figured out that there wasn't that many people there to do the same thing"

"Their supporters are fantastic, they'll travel well at the weekend I'm sure like ours did last week."

That experience of travelling the length and breadth of the country has given Sexton something of an insight into the French psyche.

"Yeah, big time, it was slightly different for me in Racing," he said.

"We used to enjoy the away games because the atmosphere was incredible, whereas our home games, at the time we used to play in Colombes.

"I don't know if you remember that stadium but I was told we were only going to be there for six months in my first year of my contract and then we were going to the new one [Paris La Defense Arena].

"So we used to love playing away but again, the team selections and stuff like that, they viewed the Top 14 as a marathon, not a sprint.

"They planned for the end, they did enough to get into the top six so a little bit of psyche there, how much it means to them to play at home, all those type of things."

On Saturday’s clash, which is being billed as a battle of the two best and highest ranked countries, the 37-year-old added: "It feels like a huge game. It is a huge game. There's no point in saying anything otherwise.

"You can't just come in here and say 'it's just another game' because it's not, it's one we've waited a long time for and I've read that they want this test; to come to the Aviva and try and overturn us.

"Being number one in the world, the public or the press will do it or the opposition will, but it comes down to the performance on the day.

"If we're favourites, we're favourites. It doesn't really bother me."

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