Borussia Dortmund coach Jurgen Klopp criticised his team for not playing "determined enough" as their Bundesliga struggles continued in a 1-0 loss at Hertha Berlin on Saturday.
Dortmund endured a difficult half that saw Julian Schieber score for Hertha and Henrikh Mkhitaryan lost to a thigh injury.
"A first half like that shouldn't have happened," Klopp said. "We weren't determined enough, and that in a game where so much was a stake."
Dortmund, who failed to put a shot on target until the 70th minute, dropped into relegation playoff spot in 16th place with the loss.
Klopp's men have two chances to move up the table -- at home against Wolfsburg on Wednesday and a trip to Weder Bremen on Saturday -- before the Bundesliga's five-week winter break.
"We have another two games this year to dramatically improve our situation for the second half of the season. That's our mission now."
BVB were coming off a draw in the Champions League that allowed them to finish top of their group, but their domestic form has been a different story. They fell to a ninth defeat in their past 15 games.
"We really have to start picking up three points away from home again," defender Marcel Schmelzer said. "We always do a first step, like against Gladbach or Hoffenheim, but then screw it up again.
"It's a shame for the team and the fans. We really need to start getting results again."