Arsene Wenger admitted he will remember his 1,000th game as Arsenal manager as a low point of his career after a humiliating 6-0 defeat to Chelsea.
Wenger remains without a victory against bitter rival Jose Mourinho in 11 attempts, with the Chelsea coach having recently labelled the Frenchman a 'specialist in failure'.
Arsenal's hopes of victory over the Premier League leaders vanished inside an astonishing opening 17-minute spell, which left Chelsea 3-0 up and Arsenal a man down.
Samuel Eto'o and Andre Schurrle found the net before Alex Oxlade-Chamberlain pushed an Eden Hazard shot around the post, with referee Andre Marriner awarding a penalty but mistakenly dismissing a bemused Kieran Gibbs.
Hazard converted with ease from the spot before Oscar struck either side of the interval and Mohamed Salah piled further misery onto Wenger's shoulders.
The Arsenal boss said: "This defeat is my fault. I take full responsibility for it. I don't think there's too much need to talk about the mistakes we made. We got a good hiding today."
Wenger admitted Arsenal's chances of winning the Premier League are bleak as his focus immediately turned to Tuesday's match with Swansea.
"It leaves it (the title chances) in a very bad situation," he said.
"But we want to respond. We had two difficult away games as Tottenham and Chelsea.
"If we had played two draws we'd have two points. Having won one we have three points.
"But today is a huge disappointment, of course. When you don't turn up in a game of this stature - nobody takes that easy."