Top Indian striker and captain Bhaichung Bhutia has been ruled out of next week's Asian 2006 World Cup qualifier against Japan following knee surgery.

"He underwent a microsurgery on his left knee on Tuesday for cartilage tear," surgeon Debashis Chatterjee, who performed the procedure, said in Kolkata.

Bhutia, who hurt his knee playing for India in a tournament in Vietnam last week, is expected to be out of action for around six weeks, Chatterjee added.

Japan, who top Group 3 with a maximum nine points, thrashed India 7-0 at home in June and are expected to register another big win in the return tie to be played in Kolkata next Wednesday.