The 20-year-old began his career with Milan in 2011, when he became the youngest player to represent the club in the Champions League, coming off the bench in a group game against Viktoria Plzen.
He made only three Serie A appearances for Milan before joining Benfica in 2014. His career stalled, however, and he played only seven times in the Portuguese top flight.
"In Milan he was being trained to become something like a new (Andrea) Pirlo," said former Juventus and Italy great Alessandro Del Piero in a recent interview with Portuguese newspaper A Bola (www.abola.pt).
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"Maybe he does not fit in the style of Benfica... But it's strange. Why doesn't he play? I believe that he has the talent to impose himself in a great team... The best would be to loan him."
Palermo, who are 16th in Serie A, play bottom club Verona on Sunday.
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