Marotta says they won't hold onto Vidal against his will.
"We have already said that he is not for sale, though ultimately the desire of the player is decisive," said Marotta. "Vidal has never indicated that he wants to leave, and Juventus would sell him only if he is unhappy here.
"However, there is no reason to be here talking about it at this time."
Gazzetta dello Sport says Vidal's agent, Fernando Felicevich, is in England today and will hold a round of talks with United representatives about the Chilean's situation.
For the big stories and the banter follow us on Twitter: @tribalfootball