Ryu Seung-Woo scored an 80th-minute equaliser for the Bundesliga outfit, who failed to beat opponents who ply their trade in the German fourth tier.
In some good news, Australian Robbie Kruse returned from a long injury lay-off due to a torn anterior cruciate ligament suffered in January.
Schmidt, whose team were reduced to 10 men late on when Ryu saw red, lamented missed chances.
"All in all, we can hardly be satisfied with our performance today as we have much higher expectations," he said.
"We started really well but we were too lax with our chances."
Kruse, 25, came on with 11 minutes remaining and said it was a good, but cautious, first step in his return.
"It felt good. Of course, I was careful but it was a good first step," he said.
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