Leinster skipper Sexton must know its time to 'bite tongue'
Experienced out-half has to control his temper as well as tempo of game
French people are notorious for dismissing English speakers who do not bother to make an effort to 'parler en Francais'.
Despite the fact Sexton spent two seasons in Paris, Leinster's new captain will communicate in English with referee Romain Poite.
The curious case of Leinster deciding to move the ultimate responsibility from Isa Nacewa to Sexton was explained by the latter's illness in the earlier part of this week.
"My wife and kids were crook last weekend," said Nacewa.
"As it does, it just rolled straight through the family.
"I thought I was bulletproof and thought I wouldn't get it, but this time I did.
"I was away on Monday and there was no point risking bringing a kids bug into camp so I was quarantined by the Leinster doctors."
There is a slight worry over the fact that when the armband was removed for the purposes of planning - no one knew Nacewa would definitely make it back - there were no other natural leaders left except for Sexton, the rookie James Ryan and the Wallaby Scott Fardy.
For the record, Leinster have relied on nine captains this year in Ross Molony, Devin Toner, Luke McGrath, Jack McGrath, Rhys Ruddock, Richardt Strauss, Seán O'Brien, Nacewa and Sexton.
Even more worryingly, Sexton has not always enjoyed a positive relationship with referees during his long career.
He struggled as recently as the quarter-final when disagreeing with another French man Jerome Garces.
"It's still a work in progress for me," he admitted at the captain's run yesterday.
"When I'm not captain, you don't have that responsibility of talking to the ref.
"But, at times, in the heat of battle, it can get on top of you."
There was strong evidence of Sexton's struggle to stay calm and composed in the quarter-final, gesticulating to Nacewa to make a case here and there to Garces.
"You probably saw that in the Saracens game," he said.
"I probably let myself down a bit in terms of, you know, getting a bit angry or agitated by some of the stuff that is happening."
There is a chance the very thing that makes Sexton tick, his aggression and edge, will have to be muted.
Is this in the best interests of Sexton and, by extension, Leinster? It remains to be seen.
"It's just about biting your tongue," he said.
"Now, I've a responsiblity to speak to him in the right way.
"It's something I've had a handful of chances to do with Leinster this year.
"I've done it when Rory (Best) has gone off for Ireland.
"It is something I've enjoyed, but not something I'm overly burdened about."
For all of that, the celebrations from the Grand Slam were short and oh-so-sweet as Leinster quickly turned towards unfinished European business.
"We are lucky in that if a lot of other countries have Six Nations success, or a Grand Slam, maybe their players come back and they are not as motivated," he issued.
"Whereas with us, we care so much about playing for Leinster we were in on the Tuesday after the English game working on Saracens straightaway."
The motivation has moved on from dethroning the champions.
The cause is to reap revenge for what happened in last year's PRO12 semi-final when Leinster were thoroughly outplayed as well as making up for what happened in Lyon against Clermont-Auvergne.
"It was a harsh lesson for all of us - me, Isa - all the guys who haven't experience a semi-final defeat before," he said about Clermont.
"To experience it and realise how difficult it will be to get through it is a positive.
"You don't always have to lose to win but it does teach you some good lessons,"he added.
The Leinster and Ireland out-half carries the big losses heavier than most because he carries more of the burden than most.
The Scarlets defeat stung badly last year, coming just over three weeks after being bundled out of Europe by Clermont-Auvergne.
He was not inclined to rank them in order of the hurt they caused.
"There's lots of results that have pissed me off," said Sexton.
"Even the wins," shot coach Leo Cullen to a chorus of laughter.