The Everton striker is on a straight loan in Paris this season.
Balzaretti told Le Parisien: "He is always seen as a very good talent. He is one of the youngest scorers in Serie A history. There have always been good echoes about him in his various stages in the youth teams.
"In U21, together with Nicolò Zaniolo and Federico Chiesa, he was considered the most important talent. He was ahead of his age. It was the 1997 generation and he was born in 2000. He was already in the group. He has always been precocious, in particular thanks to his physical qualities. He was ready to evolve with more accomplished players than him.