Bayer Leverkusen "regretfully" sacked coach Roger Schmidt -- despite still being in the Champions League -- following their humiliating 6-2 Bundesliga thrashing at Borussia Dortmund.
The 49-year-old is the ninth coach to be fired by a Bundesliga club this season.
Schmidt, who took charge in July 2014, was dismissed after three straight defeats in all competitions and with Leverkusen mired in mid-table.
"In view of the current sporting development, we have come to the conclusion that a separation is painful, but unavoidable, for the further development of Bayer 04," managing director Michael Schade said in a statement on Sunday.
"I personally very much regret this because we have a great deal to thank Roger Schmidt for.
"During his term we have qualified for the group stages of the Champions League three times and he has also implemented our philosophy of developing young players into internationals and thus creating lasting values."
Leverkusen's wretched recent run started with a 4-2 first-leg defeat at home to Atletico Madrid in the last 16 of the Champions League on February 21.
Heavy defeat at Dortmund on Saturday left Leverkusen ninth in the table, 11 points from a Champions League place for next season.
The "Werkself" qualified for Europe's top competition in all three seasons under Schmidt, but have lost 11 of their 23 league games this season.
Leverkusen will have a new coach for the return leg against Atletico in Madrid on March 15 and a caretaker coach has not yet been named.