MUNICH - Bayern Munich says defender Javi Martinez will be sidelined for about four weeks following surgery to remove damaged cartilage in his left knee.

Martinez underwent the surgery in Barcelona, in the presence of a Bayern doctor. Bayern says the damage in the knee was "small."

The Spaniard will miss the Champions League match against Juventus on Feb. 23.

Martinez ruptured ligaments in the same knee in 2014 and missed nearly a year. Nominally a midfielder, he has been playing as central defender under coach Pep Guardiola.

Bayern signed former Germany defender Serdar Tasci on Monday to compensate for the injuries to Martinez and Jerome Boateng, another central defender who will be out for about three months with a groin injury.