Schalke's European ambitions suffered a setback as they were beaten at home by Bayer Leverkusen.
The Gelsenkirchen side came into the match on the back of four straight victories but could not make it a fifth after conceding first-half goals to Patrick Helmes and Renato Augusto.
An 87th-minute strike for Kevin Kuranyi was the only consolation for Schalke, who are reportedly talking to Wolfsburg boss Felix Magath about taking over at the end of the season.
The visitors dominated the first half and could have been even further in front at the break but for the excellence of Schalke goalkeeper Manuel Neuer.
The opener came after clever play from Gonzalo Castro, whose cross was tapped in from close range by Helmes.
Schalke striker Jefferson Farfan sent a powerful shot just wide in the 18th minute but the home team were struggling to create chances.
Augusto doubled Leverkusen's lead in the 27th minute after driving in from the right wing before thumping the ball home.
Schalke pushed forward in the second half but Leverkusen keeper Rene Adler was in defiant mood.
The Germany international kept out several good chances from Kuranyi until the former Stuttgart forward finally found the back of the net three minutes from time.
Ivan Rakitic found Kuranyi unmarked in the area and the Brazilian-born striker finished powerfully, leaving Adler with no chance.
Defeat leaves Schalke seventh in the table, five points behind Hamburg who occupy the final Europa League spot.
