Marcel Schmelzer has claimed that there can be no excuse for Borussia Dortmund's performance in the 3-1 loss to Hamburger SV on Friday night.
Dortmund had the chance to put the pressure on Bundesliga leaders Bayern Munich in the weekend's first game, but they were a clear second best as Hamburg claimed a surprise win.
It was just the second league defeat of the season for Thomas Tuchel's side, but Schmelzer insists that the display was not good enough.
"I think we played really poorly in the first half," the full-back told reporters. "We allowed our opponents far too much room and didn't make the most of our opportunities in their half. We made a lot of individual errors.
"We've got to look at ourselves. We expected a lot of ourselves following the international break and didn't deliver on what we wanted to do."
Dortmund return to action against FC Krasnodar in the Europa League on Thursday night.
