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BERLIN, Aug 14 (Reuters) - Bayern Munich's Javi Martinez will undergo surgery and is out for the rest of the year after tearing cruciate ligaments in his left knee in Wednesday's German Super Cup defeat by Borussia Dortmund, the German champions said on Thursday.
The holding midfielder will fly to the United States in the coming days to undergo surgery, Bayern said in a statement.
"Obviously I am very sad a the moment but I will come back stronger than before," the 25-year-old said.
Spain international Martinez was taken off on a stretcher with his knee heavily bandaged after an attempted bicycle kick with Dortmund defender Marcel Schmelzer marking him in the 29th minute of the game Bayern lost 2-0.
The injury came as Martinez was preparing to play the central role in a new-look three-man defence with the Bundesliga season starting next week.
The Bavarians were already without Thiago Alcantara, still to return from an injury sustained months ago, while defender Rafinha has also been ruled out for several weeks.