The Gunners lost the London derby 1-0 at the Emirates Stadium after playing the majority of the game with ten men following the red card received by Per Mertesacker.
The defeat saw Arsenal drop from top spot to third but Flamini was not getting too perturbed.
After the game, the Frenchman said: "We are fighting for the title and it is frustrating.
"We gave it everything and it was not easy today against 11 men but what can I say?"
When asked if the title challenge is still on, he added: "Of course. It is a long run and we still have to fight and move forward. It is only a game but today is frustrating and a disappointment."