This was probably the biggest game of Arsenal's season. To come out of it with a 2-1 defeat is a huge blow to Arsenal's ambition of finishing in the top four.
In many ways, it was a familiar experience for the Gunners: they dominated for long periods, but were undone by some dreadful defending.
There were, however, six new things we learned during the course of the game. Go to the next slide to discover the inferences we can draw from this derby defeat.