Thomas Tuchel admitted Chelsea were given a major wake-up call after insisting they only have themselves to blame for the defeat.
Tuchel suffered a major blow to his hopes of guaranteeing a top four place which comes just three days before the FA Cup final on Saturday.
Blues boss Tuchel said: “It’s a bad thing – I don’t need these things to wake up to know how hard it is, I don’t need to lose to know this, we needed to wake up again together but I don’t know why. Now everybody is awake again.
“We were 1-0 down because we forgot to score at the other end and then scored an own goal practically, I don’t know how Arsenal would’ve scored if we didn’t give it to them ourselves.
“It was a lucky win, it was not a deserved win for Arsenal.
“I’m not happy with what I saw, I have my responsibility because I picked the line-up, but the performance was the performance.
“Totally our fault, nobody else’s. We lost, it’s totally our responsibility. We had huge chances. We made an own goal more or less – total gift.
“Overall we were not sharp enough. We couldn’t put out the same intensity and energy as usual.
“It was maybe too many changes from the last match and I take full responsibility for that. Maybe it’s the last wake-up call for all of us.”
Tuchel also claimed Chelsea should have had a penalty after Rob Holding blocked Mason Mount’s first half shot. “It was handball and there was not even a VAR check.”
Arsenal boss Mikel Arteta said: “The attitude of the boys and the team was extraordinary. I am very happy – it’s good we won one football game so I’m happy. It was a big message.”
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