On Thursday, Donnarumma made his senior Italy debut in the 3-1 friendly defeat to France, becoming the youngest ever goalkeeper for the Azzurri.
“He seems to intelligent and cool-headed," Di Canio told Milan TV.
“He has incredible qualities. Sinisa Mihajlovic did really well to immediately throw him into the 'grown-up' football. He is touched by God, truly, and if he continues like this then he'll be the natural heir to Gigi Buffon.
“Goalkeepers like Donnarumma are born once every 50 years. Milan have an iron curtain in their hands."