The stinging attack came from Napoli president Aurelio De Laurentiis, who believes the tournament should be for youth players willing to showcase their talent, and not for established stars.
De Laurentiis' comments comes just days after he warned Uruguay that action would be taken if they continued to risk Napoli striker Edinson Cavani, who recently suffered an injury at the Copa.
"If I were Messi I would say I am not coming. Take me to court, ban me, but I am not coming to disgrace myself because I am great player. I play for Barcelona, and I am not coming to play for some idiots who don't know how to play me," De Laurentiis said, as reported by Sky Sport Italia.
"Messi is a cretin. He disgraced himself by going to the Copa and he made a mistake."
Argentina were one of the favourites to win the South American tournament, but the hosts crashed out in the quarter-final stage with coach Sergio Batista receiving the brunt of the criticism for his lack of tactical nous.
"How can a player who is used to playing in one way, adapt to another way and play to a system and players he is unfamiliar with in such a short space of time? I am against it."
Speaking of Ezequiel Lavezzi, who has been linked with a move away from Napoli, the chief said: "I don't know if he will stay, ask him. It depends on him.
"Lavezzi is a madcap. There were writers who were like this, in football he is like this."
Reports claim Lavezzi has a €32 million release clause in his contract which expires in 2015.
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