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.
Milan have now confirmed that he will require surgery, meaning he faces a long spell on the sidelines.
"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."
Montolivo has been blighted by a succession of injury problems in recent seasons.
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.