Ringrose and Tracy both impress on their debuts
Garry Ringrose was just one of the magnificent eight to make his international debut against Canada.
He took a pragmatic view on his impact.
"You've got to make the mistakes to learn from them," he said.
"There was eight of us involved making our debut, so a lot of the senior players stood up and made their voices heard as well as the coaches demanding and expecting nothing but the best out of the younger guys - whether it be one cap or a hundred caps."
The mental preparation for what was a dream fulfilled was different from Chicago.
The week before there was no guarantee Ringrose would make his entrance in unfamiliar surroundings.
"I suppose the game starts earlier on in the week," he said.
"The game effectively starts on Monday as opposed to at 7 on a Saturday.
"You really got to know your detail and learn your role in different areas in what is expected of you.
"They load the week early on in training and they really do taper off so you've got to be physically and mentally ready to go on Saturday."
There was almost a try to celebrate from a fine line onto a ball thrown half-a-foot forward and another slicing thrust that revealed his cool-head in waiting for the support of Keith Earls.
Unlike the starters Ringrose, Billy Holland and Jack O'Donoghue, James Tracy was one of five with time enough to let the occasion get to him when informed he would enter the fray on the hour.
"There were about five minutes that I had to get ready, simmer on the side," he said.
The Leinster hooker dealt with it well enough to accrue a personal record of played one, won one, scored one from the final try.
"The more emotionally invested you get, the worse it is," he said.
"You want to bring a bit of emotion. You can go too far with it - whatever floats your boat.
"For me, I try and be more settled because once I am in there I have no problem getting the emotion in there."