After watching Borussia Dortmund held to a 0-0 draw by Cologne, Jurgen Klopp felt his team were not up to their usual standard.
Cologne stifled Dortmund throughout Saturday's Bundesliga clash at Signal Iduna Park, and even created the better chances with their pace on the break.
Klopp told Sky Sport: "Other teams have been struggling against Cologne.
"The very brightest moments were not there today, standards were okay, but overall too little. In the second half we were consistent and dynamic, but the lightness in the legs was gone."