Wenger told arsenal.com: "It would have been even more disappointing if Chelsea had won. We don't have to look at the results of the other teams, we have to turn up with our own performance and we didn't do that. If we play like that we cannot look at performances of the other teams.
"Of course it an important game when you play at Chelsea. I believe that today's game was an exception - until today we had very, very good games. I didn't recognise my team today and we have to sit down together to analyse what happened.
"Something is unexplainable in such a poor performance. It is always difficult to [sense it before the game] but something was not right and it is unusual to see a team as flat as we were today."