Flanker CJ Stander climbed off the bench to steer Ireland to a slender 23-20 victory over Fiji on Saturday, taking the captain's armband from Rhys Ruddock when joining the fray.
The 27-year-old admitted his honour at his captaincy cameo, then called on Ireland to refocus quickly to face the powerful Pumas this weekend.
"It's a learning experience for everyone; you learn a lot if it's not a big margin," said Stander, of the tight victory over Fiji.
"I think you learn a lot from each other and as players. As we look back, the main turnovers were in the first half.
"We just need to look after the ball and make sure we get through a few more phases and control the game the way we want to play it. Just look after the breakdown. A few times they got in there and slowed down our attack to put us on the back foot.
"I was excited (to be captain). When you get a call to go on it's a massive honour, I just said to the referee: 'I'm CJ Stander and I'm the captain now'.
"And I said about the breakdown what I felt was going wrong. He said 'perfect' and we went on.
"You just make yourself known so he knows who you are and if he looks for you he knows where to find you.
"Argentina are a physical side. Their forwards especially run hard. They play well, there's a lot of continuity in the team, they know each other very well and they're not afraid to attack from anywhere and even go up in an aerial battle.
"The set-piece is going to be important because when they snap and get a turnover they're going to punish you."