Former Juventus midfielder Alessio Tacchinardi says they should never have re-signed Paul Pogba last year.
Pogba has been provisionally suspended after testing for testosterone this week.
Tacchinardi said: "Many other players, when they returned to Italy after many years, had a similar parable.
"Kakà, Shevchenko and Vidal come to mind, but there are many others. Beyond this doping issue, I would have looked for a more solid midfielder in any case because it was clear that he wasn't the same player as before.
"And to get those figures you have to be a (Adrien) Rabiot, who plays 40 games of solidity and intensity."