And the match-winner has not only credited Messi as giving the players a confidence boost with his words of wisdom, but also advising him to push forward as much as possible in his rousing talk.
The Spaniards take on hosts Russian Federation in their round of 16 game.
"This is the first time (the fair play rule) has been used in a senior World Cup in this way".
Croatia face a defensive Denmark side in the last 16 and it is a match that will test their ability to pry open a tight defence.
"We know the team from 1998 was great, they were all our idols and they showed the way for each Croatian team afterwards", Rakitic said.
Having already said Argentina's defeat against Croatia was everybody else's problem, not Messi's, it's quickly got to the stage that Sampaoli is talking about his star man with more reverence than Real Madrid coaches are forced to talk about Cristiano Ronaldo.
Argentina is clearly not among the best teams in this tournament.
And, again, even with that now effectively the case, it nearly doesn't matter.
The 58-year-old manager has already come under heavy criticism at the World Cup, with rumors circulating that the Argentina players have started to take control of the dressing room due to Sampaoli's tactics. They went ahead as the five-time Ballon d'Or latched on to an Ever Banega through ball before slotting home with his right foot.
"To say I am devastated would be an understatement".
"What is important is the whole team defends together, not just as individuals or the midfield player in his area". We wish him all the best for the rest of the World Cup.