Arsene Wenger has spoken to discuss the Gunners dropping points against Anderlecht.
Arsenal were stunned to let a three goal lead slip against Anderlecht, and only managing to draw 3-3 with the underrated Belgians.
The Gunners conceded three goals in the last half an hour, and manager Arsene Wenger has picked out the key turning point.
He cites the withdrawal of captain Mikel Arteta through injury as the pivotal moment, but did not excuse his team from their woeful defending.
He told Arsenal.com: "I think when we lost Mikel Arteta we lost out because he was one of the few who defended well. That didn't help.
"Apart from that maybe we underestimated subconsciously Anderlecht and got punished. In the Champions League you need to be at the mental level or you get punished and certainly we were not."
Arteta had been important during the 61 minutes he was on the pitch, making three tackles and two interceptions, and completing 94 per cent of his passes, and scored a first half penalty.
That ability to retain possession would have been vital for Arsenal late on. His replacement Mathieu Flamini completed 86 per cent of his passes, made no tackles, and one interception.
Now Arsenal need to prepare for potential bad news with Wenger unable to confirm how long Arteta stands to miss through injury, but he did confirm the blow:
"He has done a hamstring. I don’t know what is wrong or how long he will be out for."
It's almost certain he will miss the tricky away game to Swansea City at the weekend, and then will have the international break to try to recover in time for the visit of Manchester United on November 22.