Mikel Arteta was left frustrated by our slow start on Sunday after an early goal made the difference for Manchester City.
Raheem Sterling scored it with a header and our manager knows that we can't afford lapses like that.
"It's really frustrating because we talked about it, that we had to come out of the blocks really strongly, really convincingly," he told Arsenal Media.
"We did the opposite and we allowed them some time around the box, sometimes with Sterling in the middle of the box with a header... against City, if you want to win you cannot do that.
"I think after that we tried to react in the best possible way. I think we matched them up, we had some really good moments, we created some great opportunities but we lacked the quality around the box to find the right pass and the right man to score the goal.
"Against this opponent, everything has to be perfect."
There was no faulting our attitude and effort against a side that looks destined to win another Premier League title. Incredibly this was City's 18th consecutive win in all competitions.
"To play the way we did today, with that personality, with that courage, to match them the way we've done, is really difficult," said Arteta.
"I've seen many other games in the last few months of theirs. It's something to be proud of but obviously we are disappointed because we got nothing from the game.
"Apart from the first 10 minutes that we didn't do something we talked about when we suffered - they used it a couple of times and we were exposed. After that, we corrected it, looked much better and much more comfortable."
There was one more positive in defeat - 90 minutes each for Kieran Tierney and Pablo Mari.
"That's crucial because we're going to need everybody," said Arteta.
"At the moment we have players that are struggling recovering from game to game. They've played a lot of minutes, you could see the fatigue in both teams at the end. The boys are trying and are working extremely hard, so I cannot demand too much of them."
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