Atletico Madrid have announced that goalkeeper Jan Oblak will undergo surgery on his dislocated shoulder.
Oblak suffered the injury during the first half of Atletico's 3-0 defeat to Villarreal, and the Slovenian international is now expected to be absent until April.
A club statement read: "Jan Oblak underwent radiology tests and an MRI which have confirmed that he is suffering from Bankart lesion in his left shoulder as a consequence of dislocation. He will have to undergo surgery in the coming days."
Oblak has established himself as the first-choice goalkeeper at Vicente Calderon, with the 23-year-old going on to make 95 appearances since signing for the club in 2014.
Experienced deputy Miguel Angel Moya will now come into the team in Oblak's absence.