“We made mistakes and they took advantage of it” he told Sky Sports.
“They were sharper than us in the final part of the game. It’s difficult to swallow but football is 90 minutes [long].”
The defeat leaves the Gunners six points behind league leaders Chelsea and virtually out of the title race.
“I don’t have to describe how annoying it is."
“We have to continue to fight" he continued.
"Today is a game we couldn’t afford to lose but we have to continue to fight.”
Attention will focus on the mistake made by the Gunners Polish keeper Lukasz Fabianski with the score at 2-1.
The Frenchman admitted that the stoppers mistake was a major turning point, adding: “I think he [Fabianski] would accept that as well."