AC Milan have confirmed Chelsea starlet Marco van Ginkel has suffered a sprained ankle and ligament damage on his first appearance for the Rossoneri.
Van Ginkel, who joined the Serie A giants on a season-long loan spell this summer, tore his anterior cruciate ligament last September just months after arriving at the club, and spent most of the season on the sidelines.
The Blues allowed the 21-year-old to leave the club to gain some first team match experience this term but the midfielder was forced off the pitch during Tuesday's league meeting with Empoli.
A statement from Milan read: "AC Milan would like to communicate that in the game against Empoli, Marco van Ginkel sprained his right ankle and has suffered some ligament damage.
"At this stage [it is] unclear how long he will be out for."
Van Ginkel lasted just 31 minutes on his debut before being replaced by Giacomo Bonaventura. At that point in the game Empoli had already opened up a 2-0 lead over Pippo Inzaghi's side, only for Fernando Torres to inspire the away side to salvage a 2-2 draw.
Torres, on a two-year loan deal from Stamford Bridge, pulled one back via a looping header before Keisuke Honda levelled on the hour.
Both Torres and van Ginkel have joined up with Michael Essien at the San Siro this season. The Ghanaian powerhouse brought an end to his nine-year affiliation with Chelsea when he joined Milan on a permanent deal in January, and the 31-year-old is confident Torres can rediscover his once-feared goal-scoring form in Milan.
"I really hope [Torres] does well for Milan and for himself," Essien told Fifa's official website. "Because he is a top striker and we will benefit from his goals. He is a hard worker both in games and in training and that can also serve him well at Milan.
"One thing Milan can expect to see is 100% all the time from him. I am convinced we will see a lot of goals from Fernando."