Leinster 40 Scarlets 32
A trademark Johnny Sexton death-stare, along with some choice words, were aimed in Scott Williams' direction. The Scarlets centre responded in kind, suggesting that the Leinster out-half keep his mouth shut.
The defending champions were on the ropes; 10 points down with less than a half an hour to go, Williams must have felt he had finally rattled Sexton with a heavy tackle that saw his arm slip up around the Leinster man's head.
It didn't look intentional. The referee agreed, but Sexton didn't exactly see it that way.
The 32-year old had already put in a masterful performance as he dictated matters on his own terms, so it would have been no surprise if Scarlets felt they could have used it to their advantage.
Instead, Sexton dusted himself down and arrowed a perfect touch-finder a metre from the Scarlets line. What followed was yet another example of Leinster's devastating clinical edge, as Sean Cronin dived over for a third try that ultimately killed off the Scarlets' challenge.
Sexton's mental resolve can never be questioned and Saturday's sensational display was the latest reminder that Leinster and Ireland supporters are watching a truly gifted player in the prime of his career.
"I just said to him that there were some massive moments in the game that he contributed to," Stuart Lancaster said.
"The James Lowe try I thought was exceptional, his hands on the short side, his vision to see it. The kick to the corner for the maul try was a huge, huge moment. His conversion of the try on half-time.
"Of all the players I've coached, he's probably the best. I've coached some brilliant players in England, obviously, worked against players.
"His ability to see the game, his knowledge, his ability to inspire others, to get the best out of them. His drive to succeed and want to achieve things is a challenge. But I love the challenge."
The 'challenge' Lancaster referred to is how Sexton demands certain standards of himself and those around him.
It is no exaggeration to say that those demands have played a major role in propelling Leinster to an historic season that has been a joy to watch. It's a long way from Sexton questioning the culture of the club two years ago.
This team has proved they can beat anyone, regardless of the conditions, and it is now up to everyone else to cut the gap.
"Yeah, that's been the pleasing thing," Sexton, who kicked 13 points, reflected.
"I think a lot of these young players have learned a lot from the international coaches.
"We're very lucky with them and then obviously in Leinster, a lot of these lads are adding to the game-plan, to the tactics, and they are understanding everything a little bit better.
"That's been the difference this year. We probably tried to do the same thing over and over again last season and we came unstuck in a couple of semi-finals when teams kinda figured us out. To change things up at times this year was brilliant. And that's the sign of a winning team."
The contest was as good as over by half-time as the Leinster pack, led by Tadhg Furlong and the unsung hero of the season Devin Toner, obliterated the Scarlets for the second time in a matter of weeks at the Aviva Stadium.
Tries from Toner and James Lowe, which Sexton's exquisite vision and skill created, had Leinster 21-11 in front.
"I genuinely feel the margins between a season like this and last year are so small," Sexton maintained.
"You go back to your couple of moments against Saracens, in the England game, they go slightly the other way and you end up with nothing like last year.
"The good thing is we learned from it. We've learned from every game. We got better. We spoke about trying to get our best performance today. It will take a couple of days to sink in, but it's been an incredible season."
Three second-half tries from Cronin, Jack Conan and another special effort from Jordan Larmour were enough to ensure that a late Scarlets fightback, including a hat-trick from the impressive Johnny McNicholl, proved scant consolation.
"I thought we got the balance right between trying to get up emotionally for last week and this week," Sexton added.
"This week was about trying to calm guys. There was obviously no lack of motivation with trying to send a couple of the lads off with another trophy and obviously with a bit of history at stake as well.
"For the next couple of days, we're definitely going to enjoy it. What we have achieved has been remarkable.
"To come off the back of the Six Nations and for everyone to stay motivated to come back and do well for the club has been outstanding.
"You do have to enjoy it. We're going to have to refocus again. The international coaches, I'm sure, will get us ready for a big Test series down in Australia."