Cronin battles against Best odds
Ireland v Canada, today (ko 7.15), live rte 2 / Sky Sports 3
Seeing really is believing. Joe Schmidt would not have extended his stay were it not for his studied opinion that Ireland will have what it takes to make a real impact at the 2019 World Cup.
This was rammed home to the wider world when Ireland removed the 'monkey' that was New Zealand from their backs and forwards last weekend.
All this time, the coach is building depth with Garry Ringrose, 21, Jack O'Donoghue, 22, and Billy Holland, 31 making their debut this evening.
There is also a brigade of five set to join them from the bench, namely James Tracy, 25, John Ryan, 28, Dan Leavy, 22, Luke McGrath, 23, and Niyi Adeolokun, 26.
It is the first of these, Tracy, who will interest Seán Cronin most as the Leinster roster alone is stacked with four fine options at hooker, including Richardt Strauss, admittedly injury-prone in recent seasons, and Bryan Byrne.
This is an embarrassment of riches for Leo Cullen and Schmidt in behind Rory Best, who wears the captaincy so well, with Connacht's Tom McCartney on track for Irish status too.
"You get a chance to put on the jersey again," imparted Cronin.
"There is huge motivation for a lot of lads, getting a massive opportunity from the start and off the bench.
"It is a really exciting mix of youth and lads that have been there for a while."
The one-two of Best as a tone-setter at the set-piece and on the fringes of ruck and maul and Cronin for his lifting of tempo and explosive impact is well-defined.
Former loose-head Tracy is something of a hybrid, not quite as dominant as Best in the tight, not quite as piercing as Cronin in the loose.
Then again, the ex-Newbridge College pupil would contend his particular set of skills make him superior to Best in the loose and physically more imposing than Cronin at the set-piece.
"He is just another one of those exciting young players coming through," said Cronin.
"Yeah, it's driving competition. You can see how competitive it is in Leinster with Richardt there as well and Bryan Byrne.
"It is no different in here (Ireland) really."
There are the young men in his position, desiring the shirts one-to-fifteen.
Then, there is the fearless nature of those who haven't endured the same peaks and troughs as Cronin.
He has learned not to take too much notice of whether he starts or impacts.
Way back when, the Limerick man could not break through at home in Munster (2005-2008), moved to Connacht for three lean years and transferred to Leinster back in 2011.
It was there Cronin first came into contact with Schmidt.
"I'd like to think it's made me a better player, working with him in Leinster and in here," he added.
The attention to detail is now just second nature to Cronin.
"Those little things are what you're concentrating harder on and once you keep doing them it's in the muscle memory and you're doing it instinctively."
He has had to meet, greet and get over many obstacles to make it this far.
"I was rooming with Joey Carbery over there," he said, about the historic victory over New Zealand.
"It is great to see how these young lads can just switch off, get twelve hours kip no bother.
"And I was staring at the wall."
The Limerick man knows how it can all easily drift away.
Every match matters. None more than the next one.
Ireland: T O'Halloran; C Gilroy, G Ringrose, L Marshall, K Earls; P Jackson, K Marmion; C Healy, S Cronin, F Bealham, U Dillane, B Holland, P O'Mahony (capt), S O'Brien, J O'Donoghue.
Canada: M Evans; DTH van der Merwe, C Trainor, C Hearn, T Paris; C Braid, G McRorie; D Sears, R Barkwill, J Ilnicki, B Beukeboom, E Olmstead, K Bailie, L Rumball, A Carpenter (capt).