Arsene Wenger has said Arsenal lacked "experience and quality" in their 3-1 loss to Chelsea but added that Marcos Alonso's goal should not have stood.
Arsenal's Premier League title challenge was left in tatters as they fell 12 points behind the leaders after another disappointing performance at Stamford Bridge, where the Gunners have not won since 2011.
And while Wenger argued that Alonso's opening goal should have been disallowed for a foul on Hector Bellerin, he admitted that Chelsea had been the better team.
"We had the right attitude, but we lacked a little bit experience and quality maybe as well," Wenger told Sky Sports. "Even our experienced players were not at their best individually today. Overall the team gave absolutely everything until the end but we lacked some maturity in the build-up and were caught many times on the counterattack in a period when we could not afford it."
Alonso headed in Chelsea's opening goal after winning an aerial duel against Bellerin, who took an arm to the face and then landed hard on the pitch and had to be substituted.
Eden Hazard then doubled the lead after the break with a solo effort as he shrugged off Francis Coquelin and dribbled past Laurent Koscielny before beating Petr Cech with a right-footed shot.
And Cech then gifted Chelsea the third when he sent a pass straight to former Gunners captain Cesc Fabregas, who chipped it into an open net. Olivier Giroud scored a late consolation goal for Arsenal, but they never looked like getting back into the game after Hazard's goal.
"I think the first goal was 100 percent a foul. And then of course we put Chelsea in [a position to do] what they like to do, wait for you and counterattack," Wenger said. "And they do that very well, you have to say they are well organised to defend together, very quick on counterattacks. And the second goal was a little bit of a killer for us, because from then on it was much more difficult."
Wenger was forced to play with Alex Oxlade-Chamberlain in central midfield because of injuries and suspensions, and admitted that Chelsea were simply more powerful than his own players.
"Yeah they looked more powerful, I agree. But that is sometimes the impression you have as well when one team tries to make 10 passes to be dangerous and one team plays for the break. That's for sure, they have powerful players, and Hazard on the second goal typifies that," Wenger said, but rejected the notion that his team lacked resilience.
"We have the resilience, I don't question the resilience in my side. It's just today, I think it all went a little bit against us. I think on the first goal we made a tactical mistake, but on top of that we were unlucky. On the second goal we were a bit naive maybe."
And the Frenchman refused to speculate on where this loss leaves Arsenal's title chances, but admitted they now have a mountain to climb.
"Yeah of course, but I wouldn't like to talk about that right now after that defeat," he said.