Arsenal manager Mikel Arteta was 'frustrated and disappointed' after Sunday's 2-1 loss to local rivals Tottenham Hotspur.
The Gunners went ahead through Alexandre Lacazette but a costly error from Sead Kolasinac allowed Heung-min Son equalise, before Toby Alderweireld headed in a late winner.
And Arteta was gutted when speaking after what he described as a "massive blow" for Arsenal's season.
"I am disappointed and frustrated and really sorry for the boys first, because the way they played today and the personality they showed today, to come into this ground and show who we are, to nullify the opponents and press them high, forcing them to kick the ball long and defend in a low block," the Spaniard told reporters after the game.
"That's exactly what we wanted to do. But obviously, if you give the two goals away that we have given against these players, it is very difficult to win a derby.
"Points wise it's a massive blow because we know the results this weekend. But we will keep trying while we have any hope. This is who we are at the moment and we will fight in two different ways - one is the league and the other is the FA Cup - to do our best to finish as strongly as possible."
