The 21-year-old left-back began his career with Inter and had several years within their youth ranks before making his Nerazzurri debut against Dutch club FC Twente in the Champions League. He was sent to Cittadella on a co-ownership deal last summer and is now set to play regular first team football in the Serie A.
With Gazzetta dello Sport announcing the deal, the Italian Under-21 international will now provide valuable defensive cover for the Elefanti who are yet to win a game so far this season.
Donnarumma did not make a single Serie A appearance for the Rossoblu last season.
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