Manchester United have identified Joe Hart as De Gea's replacement in goal, if the Spanish goalkeeper finally leaves this summer.
David De Gea had been linked with a move to the Bernabeu, but Donnarumma's surprising decision to not sign a new deal for AC Milan changed everything. Real Madrid would rather sign the promising young Italian, so negotiations with De Gea have stalled.
United remain cautious and will be ready to sign the Guardiola reject if their number one keeper decides to leave.