2018 Six Nations: Ireland's young stars aiming to light up tournament
The 2015 World Cup quarter-final loss to Argentina is a seminal moment in Joe Schmidt's tenure as Ireland head coach.
Ireland went into the game without Paul O'Connell, Johnny Sexton, Peter O'Mahony, Sean O'Brien and Jared Payne while Tommy Bowe limped off during the opening quarter.
In the aftermath of that defeat, Schmidt lamented the paucity of experience in his starting team and his squad's lack of strength in depth.
It is a lesson he has not forgotten.
Since that chastening day in Cardiff, Schmidt has dedicated himself to expanding the pool of players available to him before the 2019 World Cup in Japan.
"You have always got to be trying to spread the net and then invest in those guys so that they get as comfortable as they can in the Test arena," said Schmidt.
The average age of the Ireland squad at the 2015 World Cup was 28.2 years and that was reduced to 27 for last year's Six Nations and for this year's championship, the average is down to 26.5 years.
The shift in age profile has ushered in a new generation of Irish stars, who could light up this year's Six Nations.
|Age: 20||Position: Full-back/wing||Caps: 0|
The youngest of Ireland's next generation, Larmour has exploded onto the rugby stage with a series of exhilarating performances and astonishing tries this season. His ability to step off both feet without losing acceleration makes him unpredictable for opposing defenders.
He is the only uncapped player in Ireland's Six Nations squad and has already been rewarded with a full-time contract by Leinster after making 14 appearances for the province since his senior debut in September.
A former underage hockey international, Larmour was barely seven years old when Ireland captain Rory Best made his Test debut in 2005.
|Age: 21||Position: Second-row||Caps: 4|
Last summer Ryan emulated a certain Brian O'Driscoll when he became one of those curios of Irish rugby - a player who won a Test cap before making his first provincial appearance.
The 6ft 8in lock was captain of the team that finished as runners-up behind England at the 2016 World Rugby Under-20 Championship, a campaign that also featured a famous win over New Zealand.
Ryan made his debut for Leinster in their opening Pro14 game of the season against the Dragons and featured in all six of their European Champions Cup pool matches.
|Age: 21||Position: Full-back/Wing||Caps: 4|
After making his senior debut for Ulster as a teenager in January 2016, Stockdale's career trajectory has followed a steep upward curve.
His knack for try-scoring, which has seen him score 17 in 36 appearances for Ulster, has transferred seamlessly to the Test arena - he has scored four times in his four caps since his debut against the US last June, including a man-of-the-match display against Argentina in November.
|Age: 22||Position: Tight-head prop||Caps: 3|
Alongside Ryan and Stockdale, Porter is another graduate of the team that made it to the final of the 2016 Under-20 Championship, where he played as a loose-head prop.
A powerful scrummager and explosive ball-carrier, Porter's progress to the senior ranks was only stalled by the decision to move to the opposite side of the scrum. Leinster, who can call upon the likes of Cian Healy and Jack McGrath, suggested that Porter make the switch to the tight-head side.
Having learned his new trade under the guidance of Tadgh Furlong, Porter has already won three caps since making his debut against the USA last summer.
|Age: 22||Position: Fly-half/Full-back||Caps: 6|
An elusive runner and versatile playmaker, Carbery was plucked from relative obscurity when he impressed former New Zealand coach Graham Henry during pre-season training with Leinster in 2016. Within months he was making his Test debut during Ireland's famous win over the All Blacks, coming off the bench in Chicago to convert Robbie Henshaw's decisive try.
Seen as the long-term successor to Johnny Sexton in the number 10 jersey, Carbery has only just returned to action after breaking his wrist during Ireland's win against Fiji in November. He has had limited game time at fly-half this season as Leinster have preferred to use him at full-back.