Thomas Tuchel believes that unnecessary turnovers cost Borussia Dortmund two points as Darmstadt struck late to earn a 2-2 draw at Signal Iduna Park on Sunday.
A second-half double from Pierre-Emerick Aubameyang looked to have secured the win for Dortmund, who fell behind to Marcel Heller's first-half volley, but Aytac Sulu earned the visitors a point with a tidy finish in the final minute of normal time.
Tuchel felt his team were robbed by the late goal, but also admitted that they did not show the requisite composure to see out the game.
"We deserved to win this game. In the final minutes we had unnecessary turnovers," Tuchel said in his post-match press conference.
"Our two goals were outstanding. I was impressed with the tempo in the second half.
"The fact we have been punished in this way leaves a bitter taste. We are very disappointed. It feels like we lost two points."
Dortmund were frustrated for long period by Darmstadt's resilient, deep defending and the coach refuted suggestions that they were unable to find a solution.
"We have played against lesser opponents several times and scored 21 goals, so we find solutions," Tuchel added.
The result leaves Tuchel's men four points adrift of Bundesliga leaders Bayern Munich, who they visit next Sunday.
However, the former Mainz boss insisted he is only thinking about Thursday's Europa League clash with PAOK.
"The focus now is on the game in Salonika," he added.
