"I'm satisfied with our reaction in the second half. But the way we presented ourselves in the first half, you cannot win a Bundesliga match let alone a cup game away to Bayern," Stoger told ARD after the match.

The 51-year-old Austrian had to make do without centre-forward Pierre-Emerick Aubameyang, who was ruled out due to hip problems. With his most prolific striker missing, Stoger brought in centre-back Marc Bartra into the team in order to start with a back-five. The extra defender, however, did not add defensive stability to the Dortmund side as their passive approach saw Bayern Munich take full advantage.

When Jerome Boateng's header opened the scoring in the 12th minute, Bayern's lead was long overdue. The hosts created a barrage of changes from the first whistle, as Dortmund's players failed to close down their rivals with rigor. BVB keeper Roman Burki denied Bayern a couple more goals before Thomas Muller doubled the scoring three minutes before half-time. The Bayern midfielder could pick his corner after shaking left-back Marcel Schmelzer off his heels.

"Our passing was atrocious, we were non-existent in tackles and failed to show any courage whatsoever. After that first half we had to be glad to trail only by two goals," Stoger said.

"We found clear words in the locker room and improved a couple of things after the break."

The interim Dortmund coach adjusted his approach as soon as the 35th minute by bringing on midfielder Mahmoud Dahoud for Bartra and switching from a 5-3-2 to a 4-2-3-1 formation.

As Jupp Heynckes' team stepped off the gas significantly in the second half, the visitors managed to impose themselves on the match, mustering 60 percent possession. In the 77th minute Ukraine international Andriy Yarmolenko converted Dortmund's new-found dominance into a goal to give his team a lifeline. In stoppage time, substitute forward Alexander Isak had the chance to send the match into overtime but placed his shot wide.

"Our body language was much better and I thought that we were finally ready to play despite the tough outlook," Stoger said. "With a bit of luck, we could have turned the match around but, frankly, Bayern were the better team over 90 minutes."

Team captain Schmelzer, meanwhile, addressed similar issues as his coach, saying after the game: "In the last game of the year, a cup match against Bayern, you mustn't avoid tackles.

"We did better after the break and could have forced overtime with a bit of fortune. We failed to do that. Now we are eliminated [from the cup], which is vexing."

The Bundesliga will go on a three-week hiatus, giving Stoger time to improve his team before Dortmund will host VfL Wolfsburg on Jan. 14.