Arsene Wenger has conceded that Borussia Dortmund were deserved winners in the Champions League on Tuesday and described Arsenal's performance as "very average".

The Gunners lost 2-0 in their opening Group D game, with goals from strikers Ciro Immobile and Pierre-Emerick Aubameyang giving Dortmund victory in Germany.

Wenger had no complaints about the result and admitted that his side were not up to standard.

"I think we were not at the requested level tonight. They deserved their win," he told Sky Sports News.

"I still believe that on top of that, we were a bit unlucky as it was a throw-in to us 10 seconds before half time. We conceded the goal just after that.

"Despite our very average performance, we had plenty of chances. That's a little bit of a paradox. We could've been leading the game, but they had plenty of chances too."

Arsenal are bottom of Group D after Anderlecht drew with Galatasaray in the other week-one fixture.