'Special talent' Ryan destined for the top from an early age
Six months before James Ryan led St Michael's College to their first Junior Cup title in 10 years, there was talk that the then 15-year-old was already good enough to play for the Senior team.
The likes of Dan Leavy, Ross Byrne, Ross Molony and Rory O'Loughlin were part of the Michael's side that completed an historic double for the Ailesbury Road nursery in 2012, but even back then, they couldn't believe how highly Ryan was regarded.
Playing as a No 8, Ryan used every bit of his frame to his advantage. His time spent playing in the back-row continues to stand to him now, as was evident in Paris on Saturday in the manner in which he carried powerfully and tackled tirelessly.
"There was always an expectation that he would go on to a level that no one really in the school had gotten to before," O'Loughlin recalls.
"There was even talk, when I was in sixth year, that he would have been good enough to play for my team. At the time, you are like, 'There's no way.' But maybe he would have been.
"When he is a 15-year-old, you don't really want to believe it when you're 18.
"It was just the size of him. He was a tall, skinny guy with the frame to fill out.
"That's always the risk when you hype up a player at a young age that they might not grow, or might not get to the size to play professionally.
"But he always had the attributes to go on and make it. There have been speed bumps along the way with the (hamstring) injury and stuff. But he just bounced back.
"Now he is in a position where he is fulfilling his potential."
Leinster have known for some time that Ryan was destined for the top, but they have managed him carefully, as well as the expectations surrounding his huge potential.
The province have been down this road plenty of times before but even still, there was an element of surprise when the 21-year-old was picked ahead of Devin Toner for such a crucial Six Nations clash.
"I suppose we were a little bit surprised in here because we know the value of territory when you go to France - Dev has been a huge source of that," Leinster's scrum coach John Fogarty maintains.
"On the other side, not overly surprised because Joe likes to play lots and lots of rucks, and lots and lots of contacts. This kid (Ryan) is designed for that.
"We know how good he is so we kinda go, 'wow'. It's a departure of sorts."
Similar to Leo Cullen and Stuart Lancaster, Joe Schmidt will not want to flog Ryan.
The expectation is that he could win 100 caps for his country, but he is very new to professional rugby and is still learning how to manage his body in terms of the bigger collisions.
During his underage and school days, that was less of an issue for Ryan who was usually the biggest player on the pitch. But as Fogarty explains, it's a fine balancing act at this level.
"I think those bigger lads are aware that your body height has to be good if you are going to win a collision. He's more aware now, which is a good thing.
"Sometimes an injury can change a player. You'll see them coming from schools rugby, if they are big lads, through the U-20s into the (provincial) set-up, a bit of adjustment needs to happen. The biggest guys need to make the biggest adjustments."
Ryan has captained teams throughout his fledging career, including the Ireland U-20s, whom he led to a first Junior World Cup final.
A man of few words, at least in front of the media, Ryan is slowly emerging from his shell and O'Loughlin believes that his team-mate is becoming more of a leader.
"He is funny to have around," the Leinster back says.
"When he came in first, he would have kept to himself and been quite shy. Definitely this year he has grown and taken on a role, not a joker, but he's good at getting the best out of people.
"If someone is quiet, he talks to them. He wouldn't have a clique or a group. He takes on the music roles as well. You're not going to wrestle the speaker off him!
"You can see that he has a good way with people and he's good at getting his message across. He has the confidence in himself to be a captain.
"I have never been in a team with him as a captain. But I am sure it will come soon. Everyone who I talk to who has been led by him says he is very good at it."
Ryan's blossoming partnership with Iain Henderson was one of the biggest positives to come out of Ireland's dramatic win over France.
It offered a glimpse of the future, particularly at the World Cup next year when the dynamic pair will be expected to start in the engine room.
It was also interesting to note that Ryan played as tighthead lock last Saturday and not the more experienced Henderson, but Fogarty believes that he was born for the heavy lifting.
"He's physically really, really capable," he adds.
"He hasn't shown himself to be fazed when he's asked to play these big games.
"He's a special talent. It's amazing to have watched him go from St Michael's to the Six Nations in a couple of years.
"At tighthead lock as well, I love him in that slot. He looks really comfortable there. He gets himself into really good positions and he wants to scrummage. It's a mindset."