Italy international and Villarreal forward Giuseppe Rossi is expected to miss the next 10 months as he undergoes surgery to repair a torn knee ligament.
Rossi sustained the original injury in October, but he will require two operations to repair the problem after suffering a relapse in training earlier this month.
A Villarreal statement read: "With the objective that Giuseppe Rossi returns to his best physical condition, the most secure procedure consists of two operations."
The 25-year-old underwent his first procedure in the United States on Friday and is set to have another operation in four months, with a six-month recovery period to follow.
Rossi has been limited to nine league games for Villarreal this season, scoring three goals.