Midfielders
Argentina should fill in the midfield with as many world-class players as possible, and they do have a number of options to choose from for the same.
In this formation, Javier Mascherano and Lucas Biglia occupy the defensive midfield positions. Angel Di Maria goes on the right flank, where he is such an asset, while his PSG teammate Javier Pastore should be fielded as the left midfielder.
The number 10 role will undoubtedly go the greatest, Lionel Messi - who else could play better than him in that position? Messi can roam freely on the pitch and create chances for the front duo.
Mascherano plays in the middle of the park to make use of his experience and ability to sense the game. He can control the momentum and protect the back 3 by sliding down to the right back position occasionally. He will be partnered by Biglia, who is a very intelligent footballer. Biglia is a perfect fit for a defensive midfield position.
Di Maria has created 30 chances for his club in the league already, grabbing 6 goals and 5 assists too. He has been in outstanding form despite losing his first-team place.
Pastore hasn't played a lot under Unai Emery, but still has managed to create 16 chances and bag 4 goals to his name. Clearly, there won't be any shortage of chances created when these two play on the flanks.
On the upper side, Messi has been inhuman, like always. He has scored 20 goals in La liga and is arguably the favourite to win all the individual awards too. You just can't explain leaving him out of the playing 11. He plays wherever he wants to and wins the game for the team.
Ever Banega, Leandro Parades, and Nicolas Gaitan can be good midfield backup options.
This doesn't sound like the most balanced midfield, but there's surely something interesting that this set of players offer. During the transitions, these players can switch their positions. For example, while attacking, Mascherano can slide back to the right-back position, Rojo shifts to the left and there you have a stable four-man defence.
Whereas, Pastore can also shift inward to play as a midfielder when defending to help out the team so that Di Maria and Messi can push further up to join the attack and thus form a 3 man midfield of Mascherano, Biglia and Pastore.