Updated

Bayer Leverkusen will be without Switzerland international midfielder Tranquillo Barnetta for the next four months after he underwent surgery on his knee.

The 26-year-old sustained the injury in preseason and his absence will be a big blow to a Leverkusen side that finished second in the Bundesliga last season.

Barnetta scored two goals in 24 league matches last term for the club, which has claimed seven points from its first four games this season.