The 34-year-old is an experienced goalkeeper, enjoying spells at Villarreal, Sevilla and Real Madrid before moving to the San Siro in summer 2014.
But the Spaniard lost his place in the starting XI to teenage sensation Gianluigi Donnarumma last season, who is holding down the Rossoneri No.1 berth at just 17 years of age.
And according to Gazza Mercato, Chelsea have now agreed a deal to sign the veteran shot-stopper – but will only follow through on it should Asmir Begovic leave for Everton.
The Bosnian No.1, who measures in at a gigantic 6 foot 6, was first linked with a Goodison move in February and has since been mooted as a potential long-term successor to Tim Howard.
The Team USA international left Merseyside for Colorado Rapids this summer after making 414 appearances across all competitions for the Toffees.