Fonseca was furious with the performance after Milan's Champions League win against Crvena zvezda.
Eranio told MilanNews: "I didn't like the match either and as a coach I identify with what he said. Fonseca's words certainly weigh heavily, I'm not saying that someone is rowing against him but he's definitely not performing. If he let off steam in this way it's because he's working on a certain thing but what he says is not applied on the pitch by the players. It's one thing to try and fail, another to not try at all.
"It is difficult to manage teams of a certain level, also because the players have a power that is much stronger than that of the coach.
"The club must help the coach. Who better than him understands that the team is not doing well and that many players are not doing what he asked? If the coach has exposed himself like this, there is a reason."
Eranio also stated: "It's right to be able to do it even after a victory. Because if against Red Star you were lucky, against a superior team it ends differently. Fonseca is a good coach but it's important that the most representative players do something, because they have to give them continuity.
"Leao never went without the ball behind the lines before, now yes, he's understood. And he's reaping something. I think everyone can grow, but you have to want it."
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