THE evolution of Keith Earls from angry young man to sage leader of the Ireland team still has a way to go, but judging by his current demeanour, he is well along that road.
Earls had started the tour as centre partner to Brian O'Driscoll, but missed the second Test because of injury. That Wallace was plucked from a beach in Portugal and parachuted straight into the team in Earls' preferred position clearly rankled.
Whatever the reason, he wasn't in the mood for compromise in August and his message was emphatic.
Keith Earls "absolutely hated playing at 11" and never wanted to play there again. And not just at international level. Rob Penney had barely stepped off the plane from New Zealand when one of his star players was rocking up to his office.
Penney, obviously cognisant of wanting to keep Earls on side, did confirm that he would be given opportunity in the centre. There was a caveat, though, and the Munster coach only went so far.
While confirming that he would facilitate Earls' request "as best he could" he gave himself a large out with the addendum that it would happen in conjunction with the "best interests of the team."
Reading between the lines, it was apparent that what Earls hoped for and what Penney needed from him might not necessarily correlate. The coach did start him in the centre for his three Pro12 League games (Dragons, Ospreys and Leinster). He did little to banish the feeling that he was still a winger playing out of position.
The groin injury sustained in the Leinster match saved Penney a difficult decision. Ireland don't have the luxury of a Casey Laulala in Brian O'Driscoll's absence.
Whether it's because he is playing in his preferred position or not, Earls is now laid back to the point of being horizontal when ruminating on his positioning.
"As long as I'm fit and playing I don't really mind what position anymore," said Earls. "What I said back in August was just frustration and hatred of the performance we had in June against New Zealand.
"For me now I'm just happy to be back on the pitch. The game against South Africa was my first in five weeks, so getting through that was great. And I'm feeling sharp, I'm making my half-breaks or whatever and enjoying rugby, no matter where that is, I'd be willing to put on any jersey."
Earls' development as a person ran parallel with the growth in his responsibilities as he became a father at the beginning of the year. Before, little things used to drive him mad in the build-up to games. Now he's more in control of his emotions and approaches games more naturally.
"I used to think that if the lads saw me doing things to distract myself they might think that I wasn't clued in or taking it seriously. That's all changed now and these days I concentrate on being relaxed until 15 minutes or so before we take to the field for the warm-up.
"I'll be kicking tennis balls against the wall, laughing or, more personally, I might just go into my pictures and look at my family and daughter, stuff like that, it keeps your mind off it."
The superstitions that he was slavishly addicted to have also been knocked on the head since the start of the season and the difference in his demeanour before games has been considerable and noticeable.
"Ah, I used to have three different rosary beads and a medal, and I'd be doing things like kissing them three times, or I have to kiss one four times – that kind of craic," he said.
"But I just gave it all up, it was driving me mad. If I had forgotten my rosary beads, I'd think, 'oh, I can't play now', but they're all gone out the window."
Earls gleaned an awful lot from a visit to the Ireland camp by Olympic boxer Kenny Egan a few weeks ago. Egan's build-up routine to his fights was a massive eye-opener for Earls.
"He was saying that he's laughing and joking 15 minutes before he goes out and boxes. Then once his 15 minutes comes up, he's just thinking about the fight then, but up to that point he's joking and I kind of took that on.
"Now I prefer to just turn up on the bus and then go out and play the game. That's the kinda thing I'm trying to concentrate on and it seems to be working."
Even though he's still just 25 years of age, Earls is fast becoming one of the leaders of this 'new' Irish team.
For once, the word transition never raised its pointless head in an Irish context, but this is a changing Ireland side.
Between retirements, form and injuries, 17 of the squad that were on World Cup duty last year are not involved this month and it's incumbent on players like Earls to step up and ensure that they imprint their own indelible mark on the scene.
It's something Earls is slowly embracing: "I'm not as shy as I used to be within the squad. I feel confident enough to speak up. I'm a bit established now and, obviously, there are a lot of our senior lads pushing on a bit, so it's time for the next wave to come through.
"There's Jonny (Sexton), Jamie (Heaslip), Cian Healy, Conor Murray, we've all a few caps under our belts and it's time for us to push it on.
"You just feel when you're talking at meetings that fellas are listening to you. It's a great feeling that, hopefully, they do respect what I'm saying, because if anyone else is speaking, I put the ears up and I listen. There's nothing better than hearing it coming from the players."
Whether he sees his future in the centre or not, this weekend Earls will be tested like never before. Argentina have added a touch of deftness to their play that was missing in previous meetings between the sides, but that hasn't softened their hard edge one bit.
Earls captures it perfectly: "They're physical men. They're hard and they play hard. They're passionate fellas and we'll have to front up hard.
"They have real quality behind the scrum. We saw that in the Rugby Championship and they've obviously taken a lot from Graham Henry's involvement. We're in for a right battle, especially in the centre.
" Gonzalo Tiesi has played in Europe for a while. I talked to Mike Ross because he played with Harlequins for a while and he's a tough lad. He looks to be played with (Gonzalo) Camacho, who played with Harlequins as well, and obviously he was in the side that beat us (Munster) in the Amlin semi-final.
"Those two lads are hard men. And they'll obviously have (Juan Martin) Hernandez as well. He's back from injury and will be their key man.
"This is a pressure game. There's always pressure when you're playing international rugby and there's World Cup rankings at stake, but that's not something we've talked about. What we've spoken about is how we need the win.
"This is cup rugby and that's the mentality we have to adopt for this game."