Bayern Munich boss Niko Kovac questioned his side's attitude after they needed a stroke of luck to edge past second-tier strugglers Bochum 2-1 in the DFB-Pokal on Tuesday.
"It was all wrong for 60, 70 minutes," an unhappy Kovac said.
"The fact that we played so many bad passes, in my opinion, has something to do with the attitude ... it has nothing to do with tactics. It has to do with the attitude.
"There were too many players who played bad passes."
The Bayern boss made three changes to the side that beat Union Berlin 2-1 in the Bundesliga on Saturday, placing Robert Lewandowski, Philippe Coutinho and Muller on the bench.
But he had to call on all three in a desperate bid to avoid embarrassment in the second half, with Lewandowski coming on at the start of the second half for the DFB-Pokal holders.
Kovac felt it was his other two substitutes that changed the match, though.
"After Philippe Coutinho and Thomas Muller came on, things improved," he said.
"And in the end we got that little bit of luck against Bochum, who really played so well."
Muller told Sky: "It's a real joy to score the winning goal in a knockout game. It was a big relief. But with the big picture we cannot be happy. It doesn't help to speak and speak and speak."