Real Madrid says midfielder Xabi Alonso has a burst left eardrum and that his availability will depend on the speed of his recovery.
The club says the injury is the result of a knock received during Sunday’s 3-2 win at Valencia.
The 32-year-old Alonso was sidelined several months from the end of last season until the start of this campaign with injuries.
The Spanish league is on a two-week winter holiday break.
Madrid’s next match is on January 6 against Celta Vigo. Madrid is in third place, five points behind co-leaders Barcelona and Atletico Madrid.