Henshaw injury blow means Ireland's fringe players' lack of experience will be fully tested
It wouldn't be Argentina week without some dramatic team news to test Joe Schmidt and throw up a test of Ireland's ability to cope with adversity.
Judging by the way he flicked through the opening 20 minutes of the 2015 World Cup defeat to the Pumas without blinking at Carton House yesterday, the memory remains fresh for the Ireland head coach.
The stakes are much lower this week, but this window is all about investing in the future.
He had planned on introducing Adam Byrne and James Ryan with that in mind; losing Robbie Henshaw, however, wasn't something he wanted.
The hamstring injury suffered by the Leinster centre is unlikely to keep him out for long, and Schmidt says he could probably have pushed it if needed, but instead he's erred on the side of caution and picked Chris Farrell.
Even with Ryan involved, from Nos 1-10 Ireland are averaging 46 caps a man. Outside of Johnny Sexton, it's 16. Take Rob Kearney out of that equation and it's one cap per player.
Henshaw felt his hamstring tighten at training on Tuesday and was ruled out before yesterday's training session, meaning Ulster-born Farrell had to step in and step up. He and Bundee Aki will have had limited minutes together at Carton House; this is just his second cap.
In 2015, the build-up was cataclysmic as Paul O'Connell, Peter O'Mahony, Johnny Sexton and Seán O'Brien were ruled out. Ireland failed to handle it, players failed to perform.
In the four years in between that game and the 2019 World Cup in Japan, Schmidt is trying to infuse as much experience in as many players as possible.
Coping with late withdrawals is part of that.
"Robbie being unavailable wasn't something we'd foreseen, he would have added more experience to that three-quarter-line," Schmidt conceded.
"But part of the attraction for us is that, a little like last week, guys will have to independently survive and make good decisions - not have somebody directing them around the pitch.
"We would rather we had someone right there to assist them, but sometimes that doesn't happen - someone gets injured early in the game and destabilises them. We want to be able to play our way through destabilised periods."
Schmidt pointed to the havoc injury played during the first half against the Wallabies a year ago, and the withdrawals that hampered them against England in this year's Six Nations. Despite the adversity, they won both games.
"It's not always going to work out perfectly like that," he continued. "I suppose the more opportunities we have to test people in those situations, the more they'll learn about themselves, the more they'll be better equipped to cope in the Six Nations or further (beyond)."
His team are 15-point favourites with the bookies, who have clearly been paying attention to Argentina's terrible form-line.
The Pumas have struggled to recapture the performance levels they produced in 2015, winning just eight of their 26 games since.
"A good day in the office has to be some good performances from some individuals who we've given an opportunity in the context that we want to be cohesive as a team," Schmidt said.
Although it is only his second cap, Bundee Aki offers a fair degree of experience and rarely takes a backwards step. In Henshaw's absence, his role has become far more important.
"He brings energy but he also brings calm," Schmidt said.
"The fact that Bundee says, 'We don't do stress here, we just need to stay clear in our heads and get the right thing done' - that is what experience can do for the guys around them.
"It can keep them calm and rather than start to think, 'What decision do I take here?' because as soon as you start talking about making a decision and if it is not in line with somebody else's decision, that is where you get a fractured defensive line and that is where you get into trouble.
"Between Johnny (Sexton) and Rob (Kearney) most of the leadership will come because we are trying not to demand too much of Bundee yet."