Arsenal defender Rob Holding was left frustrated after their Europa League defeat at FC Koln.

Holding was close by when Sehrou Guirassy went down under Mathieu Debuchy's challenge, and he wasn't sure the referee got it right.

“I was on the right hand-side, so I just saw Per and Debuchy squeeze him out, push him away from the ball and trip over him. I'll have a look at it and see if it was the right decision, but first thoughts I didn't think it was.

“I haven't really spoken to him [Debuchy] about it, I spoke to Per about it and he said he pulled out of [the challenge] because he knew what he [Guirassy] was going to do.

“I think we dominated the possession and had most of the chances and got a questionable penalty decision, but that's the way it is sometimes. We tried hard to break them down, but just couldn't get that goal.

“I didn't know if the results had gone for us, but [they did] and that was the target for us, to finish top. That's a positive to take into the next round."