Gauntlet thrown to Cronin and Stockdale
The brilliance of Joe Schmidt's system is that it is truly based on the collective.
When one man falls, the next man up picks up the pieces in what can be a relatively seamless transition.
It was no more than three months ago when 35 year-old Rory Best stood head-and-shoulders above all challengers at hooker.
Two weeks into this test series, the understudies have moved to centre stage.
Ulster's Rob Herring, 28, and Munster's Niall Scannell, 26, have embraced their roles with relish.
They have been showing, in no uncertain terms, that Schmidt's master plan to put his players under pressure and keep them there is paying off in spades.
Through this process in Australia, Sean Cronin has been portrayed as the fall guy for that broken scrum in the first test.
Now, the opportunity arises for the Limerickman to show why he had Best's back in the Six Nations.
This will be his redemption or a nail in his ambition to make it to Japan next year.
The same pressure to perform weighs on the broad shoulders of Jacob Stockdale.
The Six Nations Player of the Championship is not without his flaws.
He has to learn to play to his size, be more aggressive in everything he does.
Keith Earls is Ireland's number one wing at the moment, and Andrew Conway has worked on so many of the characteristics Schmidt likes in Ireland's system.
He's nowhere near the stature of Stockdale though, so who would Schmidt back to win the ball in the air?
"It was tough sitting on the sidelines and watching it last week," said Stockdale.
"These are the kinds of game you play rugby for and I'm definitely very excited for it."
This test is about much more than just winning it. It is about how individuals come together to be better.
Ireland will have to be just as good, maybe even better than they were in Melbourne.
Australia coach Michael Cheika has made a firm commitment to open, attacking rugby in order to crack open the Irish.
When questioned about the possibility of tightening up the strategy in what amounts to a cup final of sorts, the former Leinster coach was not inclined to take a backwards step.
"I think we'll be less conservative," he said.
"You can't win finals without scoring tries and playing footy.
"I'm a true believer in that," he said.
The gauntlet has been thrown down to Cronin, Stockdale and everyone else.