Bayer Leverkusen lost further ground on runaway Bundesliga leaders Bayern Munich with a 2-1 home defeat to fourth-placed Schalke.
Leverkusen, still in second, are now 16 points behind the defending champions as Schalke extended their winning streak to four matches.
Midfielder Leon Goretzka chipped in for Schalke's opener before Felipe Santana's own goal levelled.
Leverkusen missed several chances as Klaas Jan Huntelaar headed the winner.
Leverkusen were knocked out of the German Cup by second-division Kaiserslautern on Wednesday and next face Paris Saint-Germain at home in the Champions League on Tuesday.
Bayern had earlier beaten Freiburg 4-0 to stretch their unbeaten league run to 46 matches.
"We played the better football, I feel for the team," Leverkusen coach Sami Hyypia said. "If we play like this on Tuesday I'll be happy. We showed a lot of character."