For evidence of just how quickly Garry Ringrose arrived on the international scene, you only have to ask for his earliest recollections of the Six Nations.
The precociously talented centre, who turned 22 just last week, will be making his debut in the competition against Scotland tomorrow (2.25pm kick-off) alongside some who were already internationals by the time he remembers watching his first Championship game.
Off of the famed Blackrock College production line, the famous demolition of England at Croke Park in 2007 and the dramatic Grand Slam clincher against Wales two years later are the first clashes that really stick in his mind.
He admits it is almost surreal to be preparing for his first involvement as a player so soon after.
"I would have been going to most of the home games with either my mum, dad or brothers. It is a little bit surreal, to be involved now," said Ringrose.
"Obviously the Ronan O'Gara drop goal at the Millennium Stadium is the memory that stands out, that was in 2009, so I would have been in second year of school.
"I would have been at the home games last year even, supporting. It is pretty cool to find myself involved with it."
Winning just his fourth cap tomorrow, taking the 13 jersey from injured Ulsterman Jared Payne, he at least has experience of a big game at Murrayfield under his belt - Leinster's PRO12 final defeat to Connacht last May.
He was playing opposite his now Leinster team-mate Robbie Henshaw that day, the man he'll be alongside tomorrow in Ireland's midfield, and admits he far prefers this scenario.
"Playing against him isn't too fun," he recalled. "I learned a few hard lessons that day.
"It wasn't a great day for Leinster as a club but it was a learning experience for me.
"I'm lucky enough to be playing alongside him now with Leinster and Ireland so that's even better.
"You kind of forget how young he is with the amount of experience he has. It's a luxury really at Leinster to get a chance to play outside him because he's just so good and I'm still learning off him in training and in matches, any opportunity I can."
Less familiar is his relationship with Paddy Jackson but, having played outside tomorrow's starting No.10 at some stage of each of his three caps, Ringrose believes the Ulsterman can fill the void left by Jonathan Sexton's injury-enforced absence.
"Thankfully in the autumn I managed to play a lot with Paddy and I've played against him too with Leinster," he added. "I've trained with him loads and it's important to have that familiarity right from 10 out to the wingers, having that connection and being able to communicate."
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