Dani Carvajal will have surgery in the coming days after he suffered a serious knee injury during Real Madrid's 2-0 win against Villarreal.
Carvajal, 32, was in tears as he was carried off the pitch on a stretcher following a challenge with Yeremy Pino on Saturday.
A statement from the Spanish club read: "Following tests carried out on Dani Carvajal by the Real Madrid medical services, the player has been diagnosed with a ruptured anterior cruciate ligament, a ruptured external collateral ligament and a ruptured popliteus tendon in his right leg. He will undergo surgery in the coming days."
In a message posted to Instagram, Spain international Carvajal wrote: "Serious cruciate ligament injury confirmed. I am going to have to go through surgery and be off the field for a few months."
"Already looking forward to starting recovery and coming back like a beast."
Vinicius Junior's superb long-range effort sealed Real Madrid's 2-0 home win to take them level on points with LaLiga leaders Barcelona. But the Brazilian is also an injury concern after he left the pitch holding his shoulder.
Barcelona, who remain at the summit of the table on goal difference, play at Alaves on Sunday.