Calciomercato.com says United could enter the race for Donnarumma – if David De Gea moves to Real Madrid.
United are believed to be readying a bid for Cristiano Ronaldo after the Portugal international revealed he wanted to leave Spain after tax fraud allegations.
And that offer could involve keeper De Gea moving to the Spanish giants with Ronaldo and Alvaro Morata moving the other way.
That would mean United would be in the market for another stopper and also rule out Real in the chase of Donnarumma.
The report suggests United chiefs are already looking at the 18-year-old after he told Milan he would not sign a new deal with the club.