Star Brazilian youngster Pato has signed a contract extension at AC Milan, the club s vice-president Adriano Galliani told the official Milan TV channel.
Pato joined Milan in January 2008 from Internacional and quickly established himself in the first team.
The 20-year-old has signed a deal that will keep him tied to the club until 2014 in what many see as a bid from Milan to discourage interest from Chelsea and their former coach Carlo Ancelotti in the January transfer window.
He has scored 29 goals in 68 matches for Milan and started this season in sensational fashion, scoring twice in the opening day victory at Siena.
But he has failed to find the net in four matches since and was substituted early in the second half of Wednesday s 1-0 defeat at Udinese.