The 27-year-old was purchased last summer for €14.4m and proved instrumental in the Serie A title victory, making some remarkable saves.
He is currently out injured for a month after suffering a calf strain while playing for France in the Nations League.
Dida of course won everything at Milan under Carlo Ancelotti and returned to the club as their goalkeeping coach in 2020.
“I’d put Maignan among the top six to 10 goalkeepers in the world right now, but he is improving all the time,” Dida told MilanNews.it at the presentation of a new documentary into the Ancelotti era.
“I taught him what I had learned. Coming to Milan means taking on a big responsibility. He was lacking the basics in terms of technique, so he is improving every day in that respect.”
The documentary is called ‘Stavamo Bene Insieme’ (We were good together).