The 45-year-old admits the Royal Blues were the better team on the day and put the loss down to a failed game plan in the initial stages of the encounter
The Gelsenkirchen outfit won the bragging rights in the Ruhr derby as Ibrahim Afellay and Marco Hoger both netted to cancel out Robert Lewandowski's second-half strike and increase the reigning champions' deficit behind league leaders Bayern Munich to 12 points.
After the game, the BVB coach voiced his belief that he started the match with the wrong tactics and, despite an improvement after coming back from two goals down, the Royal Blues remained the better side.
"We did not play well until we made a change to our system after half an hour," he said.
"We were a little more stable from there onwards. We played enough football, but overall it was a deserved win for Schalke."