Murray vows to keep the emotion in check for England clash
Sometimes there can be too much emotion, sometimes none at all. Conor Murray is asked about Croke Park in '07. "John Hayes crying and all that? Yeah I remember that." The 'Bull' could corral his emotions and channel them correctly.
Nonetheless, as Brian O'Driscoll recalled during the week, "You knew how important the game was when that freak was going to be crying."
Murray is just as intense but cut from a different cloth. "Conor is an incredibly quiet young man," relates Ireland coach Joe Schmidt.
"He doesn't say a lot, he is just so proficient, he gets the job done very, very efficiently."
Murray may allow emotion in; little gets out. There will only be the merest release in the lengthy, yawning build-up to kick-off time.
"When you walk out you look up at your family and that will be the most emotional part for me," says Ireland's scrum-half who, despite his extraordinary rise to global prominence in the last four years, has yet to taste victory in this fixture.
"I know where they sit usually so I will have a look up to them for a couple of seconds and just give them a wave or whatever."
It is a but a momentary diversion. The head then immediately assumes control, though the heart still pulses strongly. Waves of sentiment may lap through the pulsating crowd but he must limit those that he surfs alone.
"Then you are just switching back into the game and even when the anthems are going you are already thinking about that first kick-off. You know by then whether is it their kick or ours.
"The emotion is there but you can't think about it too much because you have an international game to play."
Jack McGrath is even less experienced and, as such, has an even more difficult tightrope upon which to balance feelings and actions.
"It's my biggest start and my biggest game ever," he admits simply. "I'm really look forward to it now. I don't want to get too excited, too early.
"It's definitely something I will remember for the rest of my life and, hopefully, it will be a good one to remember.
"It is an emotional day. Every game is emotional. This one is just that little bit more special.
"You have to keep your emotions in check where you can't lose the plot. You have to be cool in the head and have fire in the belly. I know it's an old adage. But that's it. You have to channel your emotions in a productive way. It's very hard."
The coaches can be confident their work is done and that the players selected are more than competent to deliver the technical intelligence required to deliver on each task.
But there is an added layer and this is where those in charge of emotional intelligence, like the squad's sports psychologist Enda McNulty, come to to the fore.
"That can be an issue with a lot of guys," concedes McGrath.
"Experience is a massive thing. Enda is a great help with that sort of thing, he just talks you through the techniques of breathing or just the 'next job' mentality."
McGrath's 'next job' will be to help his pack de-power the English scrum as, once again, he is preferred by Schmidt ahead of the returning Lions' star Cian Healy.
"It is great to get the nod and still brilliant to have Cian back in the squad," says McGrath.
"It's going to be one of our hardest tests for a long time. They were really strong against Wales and again against Italy so it's a massive test for us as a pack. We need to go out and meet them.
"Graham Rowntree will have them well prepped in the scrum, he will have them trying to attack us. It's up to us to attack them back.
"All English teams take pride in their scrum. They always want to force themselves as a pack. For us as a pack to be able to beat their own man is one thing.
"But we want to be able to bring into the weekend and then be able to do it all together."
The scrum must do so without Jamie Heaslip at its base; albeit, controlling a ball may be a rare deficit in the absentee's skill-set, Murray has no qualms about Jordi Murphy's ability to adapt once more.
"I suppose you've been there and done it with Jamie so many times," he explains, "you understand when he is going to take the ball out of the scrum or other scenarios like that around the pitch.
"But with Jordi, I do understand the way he delivers the ball from a scrum or what he likes to do around a scrum which is probably the main area of the relationship. That started before the Italian week and it has kept on since."
Murray's losing streak against the England nags him, particularly last year when Ireland blew a 10-3 lead with a half-hour left; they were undone by two lapses of concentration that ceded 10 points and ultimately victory.
"That defeat hurt us," he says. "And it's four years now. It's something that is annoying us as a group of players and we want to put that right this weekend.
"We need to physically dominant at the weekend."
And find the mental balance, too.