It was there in the stare. The Leinster media event had just started when Leo Cullen moved to quieten voices at the back of the class.
All it took was one word and one look.
There is a ruthless streak in Cullen that has been revealed in his selection against Munster.
It is difficult to know how Ireland wing Dave Kearney took the news that he didn't even make the 23-man squad.
It is difficult to know how Fergus McFadden would have dealt with learning he is second best to Barry Daly for this one.
Cullen has to be commended for not just talking about those in-form, but also going with them.
In a time of need, the temptation to go with who you know, from past experiences, rather than what you don't know about in a big game must be great.
Cullen has shaken that off to back the numbers totted up right here, right now.
UCD wing Daly - a late developer at 25 - has come out of left field to surpass experienced internationals.
"He did well in pre-season, played 15 minutes against Dragons, came on in the second half against Cardiff and scored that try where he made an unbelievable take in the corner," said Cullen.
"He played against the Cheetahs, scored a hat trick.
"Barry is getting picked because he's able to score tries. He's a genuine finisher. He deserves a window in one of these big games."
Daly is a winger with a point of difference, at 6ft 3ins and with a point to prove. There have been those, like Darragh Fanning, who have taken the circuitous route back to Leinster through the All-Ireland League and another province.
It is rare to witness the arrival of someone at Leinster through the AIL and a trial to earn a start in the biggest regular-season league match of the season.
"It's a great story, from the clubs, for younger players who might miss out on academy or sub-academies," continued Cullen.
"There is a way there to get through to the professional game again."
The tide is turning in favour of the younger crew, with Adam Byrne and Rory O'Loughlin also dotted along the three-quarter line.
Seán O'Brien's calf strain opens the way for Rhys Ruddock, Josh van der Flier and Jack Conan to man a well-balanced back-row.
Above and beyond the meaning for individuals, there are the precious PRO14 points on offer. Leinster should show serious signs of improvement to be ready for the Montpellier juggernaut next week.
"Munster probably have the advantage because they've probably had more continuity over the course of the last four or five weeks," said Cullen.
"But this week has been better so we're just looking to have a better level of performance."
What will that centre around?
"It's the intent," he stressed. "There are going to be very motivated players out there so we just need to make sure we're focused."
There is the charge that Leinster and Munster know each other too intimately.
The games usually boil down to inch-by-inch warfare, albeit without the rancour of yesteryear.
"The game has changed and is still changing," said Cullen. "There is the scrutiny on players.
"There is contact in a different way. Rucking is not a part of the game any more.
"People have this perception in their minds. If you wind the clock back to 20 years ago, it was different.
"The hits are a different kind of hit. The collisions are a big contact in the game.
"It has everything good about the sport but the game is different."
What would be different for Munster would be to win this fixture for the first time since 2014.
Visiting director of rugby Rassie Erasmus has sprung more surprises than Leinster.
Munster's back division is a source of interest as Ian Keatley has been rewarded for last week's authoritative performance against Cardiff Blues.
Tyler Bleyendaal is preferred to Rory Scannell as a second receiver at inside-centre.
JJ Hanrahan drops back into the pocket of isolation that is full-back, while Andrew Conway slips to the right wing, with Alex Wootton somewhat unlucky to lose out.
This is a shop window for centre Chris Farrell, who has shown an improved passing game on his return from France.
There could even be a move by Erasmus to take the game out of the hands of his forwards. Neither Billy Holland, the worker, or Robin Copeland, the athlete, are second-row material at international level.
"I wouldn't say that's a hole. They are two capped internationals," argued Jack McGrath.
"Robin, I know quite well from playing in Mary's. He's an incredible athlete.
"Billy Holland is a strong powerful player. Again, I know (replacement second-row) Mark Flanagan. I don't think any of them would be walk overs.
"We're not taking any of them lightly. A game of this level, they're going to be upping their game ten-fold.
"It's not an area of weakness that we're looking at."
That would come as a surprise given the impact of Leinster's props McGrath and Tadhg Furlong with the scrum solidity of James Tracy, preferred to the explosive bench impact of Seán Cronin.
There could be a complete reversal of roles as Leinster's forwards seek to dominate and destroy up front, while Munster look to move into a groove out the back.
Leinster: J Carbery; A Byrne, R O'Loughlin, R Henshaw, B Daly; J Sexton (capt), L McGrath; J McGrath, J Tracy, T Furlong, D Toner, S Fardy, R Ruddock, J van der Flier, J Conan. Replacements: S Cronin, C Healy, M Bent, R Molony, J Murphy; J Gibson-Park, R Byrne, F McFadden.
Munster: JJ Hanrahan; A Conway, C Farrell, T Bleyendaal, K Earls; I Keatley, C Murray; D Kilcoyne, N Scannell, J Ryan; R Copeland, B Holland, P O'Mahony, T O'Donnell, CJ Stander. Replacements: R Marshall, L O'Connor, S Archer, M Flanagan, J O'Donoghue; D Williams, R Scannell, A Wootton.