The Brazilian hitman limped off during the opening stages of the 1-1 draw with Udinese last night.

　　"AC Milan announce the medical tests undergone by Alexandre Pato this morning highlighted a right thigh strain," read a statement.

　　"The Brazilian is expected to be out of action for around four weeks, save for complications."

　　It is a heavy blow for the Rossoneri, who are already without Zlatan Ibrahimovic, Robinho, Kevin-Prince Boateng, Gennaro Gattuso, Massimo Ambrosini, Daniele Bonera, Luca Antonini and Mathieu Flamini.