bundesliga.com rounds up the players' post-match quotes from the RheinEnergieStadion.
Ilkay Gündogan: I thought I settled into the game well and I didn't get frustrated if things didn't go my way immediately. I just tried to do what the coach had told me before the game. Obviously I wish we'd got a better result, though.
Marco Reus: We didn't have enough about us in the final third and didn't have enough shots on goal. That goes for me, too. We played well until the equaliser, but missed the chance to make it 2-1. We only have ourselves to blame.
Mats Hummels: It's a massive disappointment. Going five games without a win isn't something we're used to at Dortmund, but we're not going to panic.
Roman Weidenfeller: Things just haven't been going how they should for us. Obviously it was my mistake and I've apologised to the team for it. We lost a point because of it, but that shouldn't cover up the wider issue. We've got to work hard as a team and turn things around. It's a tricky situation, but we need results. Most of the team have been here for the glory years at BVB, so the older players need to start providing a bit of calm.
1. FC Köln
Kevin Vogt: We got our just rewards today. We've played well recently but haven't managed to get the results our performances would've deserved, particularly away from home. It was nice to give our home support something to cheer today.
Simon Zoller: It's a really important win for all of us, for me personally and for the team. I'm thankful to the coach for the trust he placed in me.
Kevin Wimmer: Zolli [Simon Zoller] has worked really hard for a goal like that. We're all delighted for him.
Dusan Svento: I really enjoyed starting today and gave it my all until my substitution. I believe we were deserved winners.