The man most able to help Lionel Messi shine at the Brazil 2014 World Cup, Fernando Gago, must start every game for Argentina.
When Gago injured his left knee while playing for Boca Juniors against Colon in mid-April, there was concern that he would barely be ready for the tournament in June and July.
The 28-year-old may be a little lacking in match fitness, but he is training with the squad and it appears now he is going to be fully recovered from his knock and ready to participate in Argentina's opening game against Bosnia and Herzegovina on June 15.
Argentina XI from training: Romero, Zabaleta, Garay, Fernández, Rojo, Gago, Mascherano, Maxi (will be Di Maria), Agüero, Messi, Higuaín.— Rupert Fryer (@Rupert_Fryer) May 29, 2014
This is excellent news for Argentina coach Alejandro Sabella, who only has one player, Ever Banega, capable of carrying out the same role as Gago, and the Newell's Old Boys man has often failed to produce his best in national team colours.
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The Albicelestes probably have one of the most settled starting XIs of any team participating in the World Cup, and the midfield setup that Sabella is likely to use is all about balance.
The tenacious Javier Mascherano will be charged with protecting a mediocre defensive line by patrolling just in front of the back four, as well as distributing possession to his more technically gifted teammates from deep when Argentina have the ball.
Angel Di Maria, in the form of his life, will bomb up and down the left edge, helping out in defence and ideally providing some real spark in attack.
Gago, meanwhile, will be the man expected to most frequently link up with Argentina's key player, Messi.
The former Real Madrid player can work in tight spaces, he has a smart football brain and he is a highly skilled passer.
Part of the reason Messi's form for the Albicelestes has improved markedly over the last two years or so, is that he is now receiving better quality balls, in much better positions; and a lot of the credit for that must go to Gago.
Argentina's captain, rather than having to track back deep into midfield to get the ball with his back to goal, is now frequently fed possession in more advanced areas, where he can run at defenders and do real damage.
Messi knows he can rely on Gago to be in the right spot should he need to return a pass as well, before scuttling off into another gap that he has spotted.
With world-class strikers in Sergio Aguero and Gonzalo Higuain lurking up front, opposition defenders cannot focus all of their attention on "La Pulga," either, as Gago has the ability to play incisive through balls into the box as well.
It is an old football adage that great attacking players can't do damage if their supply line is cut off.
With Gago in the team, cutting the supply to Messi becomes far more difficult for opponents. His fitness and form in Brazil will be crucial to Argentina's success.