AC Milan boss Massimiliano Allegri admits there was little they could do to keep Andrea Pirlo from Juventus. Pirlo faces his former club on Sunday.
Allegri confirmed why Pirlo left, suggesting it was not because of contract or tactical issues.
He said: "Andrea said the truth: that he was looking for other challenges.
"When you are in the same place for 10 years, you need a change, and he is proving that on the field, understanding that last year he was great when he returned against Bologna to a mezzala role, before losing the season to injuries."