AC Milan have announced that midfielder Riccardo Montolivo damaged a cruciate ligament in his knee in Italy's draw with Spain on Thursday.
The 31-year-old was carried off on a stretcher after half an hour of the 1-1 draw in Turin, having come off worse in a collision with Sergio Ramos, and was sent for tests to determine the damage.
"AC Milan announces that, during last night's match with the Italian national team, Riccardo Montolivo suffered an injury to his left knee anterior cruciate ligament," a club statement read.
"Due to the extent of the injury, the player needs to undergo surgery."
He was denied a place at the World Cup in 2014 after suffering a broken leg and was forced to miss Euro 2016 due to a calf muscle problem.
The Milan captain had played in all seven of his side's Serie A matches this season prior to earning a recall to Giampiero Ventura's squad for the World Cup qualifiers this month.
