Roque blow for Milan
The Brazilian central defender sustained the shoulder problem during the first leg of Milan's Champions League qualifier against Slovan Liberec.
The 26-year-old landed heavily on his shoulder after a challenge and he faces three months on the sidelines.
"Our medical staff attempted a non-surgical treatment but did not find positive results," read a statement on Milan's official website.
"In accordance with the player, Roque Junior will undergo surgery in Brazil. If there are no complications he should return in around three months."
It makes Milan's signing of Italian international Alessandro Nesta a timely move as he will provide cover for the injured Brazilian.