Bayer Leverkusen goalkeeper Rene Adler is to undergo knee surgery on Wednesday and is likely to miss the start of the new Bundesliga season.
Adler, 26, will be operated on in a bid to remove scar tissue from the patellar tendon in his right knee. He injured the joint in the pre-season game with Salzburg on July 3 and says surgery is the only option.
"I have to have an operation if I want to play this forthcoming season without pain,'' he told the club's official website. "It is a major blow for us,'' said Leverkusen general manager Rudi Voller.
"We will wait and see how quickly Rene can recover from his surgery but there is no fixed date.''
Should he miss the season-opener at Mainz on August 7, either Fabian Giefer and David Yelldell will start in goal.