Villarreal have lost central defender Carlos Marchena for around a month with a torn hamstring.
The Spanish international suffered the injury during the weekend's defeat at Getafe.
He was forced off after 70 minutes and now scans have confirmed the extent of the problem.
Marchena will now miss the Yellow Submarines' next seven games - four in La Liga, two in the Copa Del Rey and one Europa League match this week.
Full-back Joan Oriol also remains sidelined with his ankle injury and he is expected to be out until after Christmas.