The Mirror is reporting the 25-year-old Brazilian striker, who is currently on loan with Sao Paulo from Corinthians, has opened talks with the Premier League club.
Pato scored 51 goals in 117 Serie A appearances for Milan, but injuries cut his time at the San Siro short.
Pato has spent the past four seasons in his native Brazil since leaving Italy.
Need a VPN? Or seeking to switch? Then support Tribal Football by clicking here to sign up with our official partners NordVPN. Not only will you receive the best VPN experience, but also great discounts by signing up via Tribal Football. Thanks for your support!