The two teams meet on Sunday.
Pioli was in charge of Lazio while Inzaghi took the primavera team.
He said, "We studied Fiorentina carefully, they are very aggressive and always take the game to their opponents. I learned a lot from Pioli. We were side by side, training at different times, so he'd often let me sit in and watch his sessions.
“He's a good person and it was a pleasure to talk to him about football. We would regularly have lunch together and I have fond memories of him and his staff."
He added: “I expect this to be a very difficult match, as Fiorentina have a lot of quality in their individuals. I know Pioli well and he prepares games the right way," said the Coach in his Press conference.