Arsene Wenger has slammed Swansea City's defensive approach and his side's poor finishing following the Gunners' 1-0 defeat to Garry Monk's side.
The north London side enjoyed a number of chances to take the lead but were frustrated by the impressive performance of former Arsenal goalkeeper Lukasz Fabianski before Bafetimbi Gomis scored the only game of the game with five minutes to go.
When asked for the reasons behind his side's defeat, Wenger told a press conference: "We were unlucky I think against a team who refused to play completely and just defended.
"It was a question of being patient enough and if we couldn't win it not to lose it. Overall I was encouraged by the quality that we showed in the second half, but it's frustrating. When you cannot win a game, don't lose it. We knew exactly what could happen. It was not even a break.
"We were warned of the kind of goal they could score with Montero kicking the ball in the air and we were short in jumping for the ball. For the rest we rushed our finishing because we had plenty of chances in the second half. It was just a question of scoring a goal."
While Wenger was impressed with Fabianski's performance he believes Arsenal's lack of a cutting edge was a key reason behind the defeat.
"Fabianski did well tonight. I believe as well on some occasions we made it too easy for him.
"We rushed our finishing. Sometimes we were maybe too eager to finish alone rather than passing the ball. Sometimes we had to force the situation and in the end you have to give them credit - they defended well."
Arsenal missed the chance to go level on points with Manchester City in second place in the Premier League ahead of their visit to Manchester United on Sunday 17 May.
Asked about the game at Old Trafford and the importance of finishing in the top three, he added: "It's very important."
"We still have a game in hand. What is crucial is to respond on Sunday and show that it was an accident today. That is the most important thing."