Schalke stunned by bottom boys Freiburg
South Korean Cha Du-ri scored Freiburg's winner five minutes before halftime after pouncing on a mistake by Benedikt Hoewedes to hand Schalke their first league defeat under new coach Felix Magath.
Freiburg survived constant Schalke pressure in the second half to hang on for their first win of the season.
Leverkusen fell behind in the 33rd minute when Argentine Diego Klimowicz scored but equalised before half-time when defender Manuel Friedrich headed in following a free kick.
Stefan Kiessling scored the winner from close range to leave Leverkusen with 10 points from four games.
Brazilian Carlos Eduardo scored five minutes before half-time to give Hoffenheim a 1-0 win at Hanover 96 while Eintracht Frankfurt were held 1-1 at home by Borussia Dortmund.