Chelsea were rewarded for their ambition and self control with a lucky Didier Drogba goal to beat Arsenal on Sunday, manager Jose Mourinho said.
"At halftime I told my players the game was so close that you must not lose your emotional control and your tactical organisation but play with more ambition," Mourinho said.
Drogba eventually broke the deadlock after 73 minutes when Frank Lampard's free kick from the right bounced off his knee and past Arsenal keeper Jens Lehmann.
It was Chelsea's first league victory over the Gunners for 10 years and vindication of Mourinho's halftime substitution of Hernan Crespo with the more direct Drogba.
"I saw two teams very, very equal in their performance, organisation and approach to the game but when you look back to the chances you will see that we had produced more chances than them," Mourinho said.
The fluke strike soured Arsenal manager Arsene Wenger's celebration of 500 games in charge at Highbury.
"We gave a very cheap goal away," Wenger said, adding his side should have been more incisive and physically commanding.
"We lacked a fraction of self-belief. I hope from this the team gets the realisation that we can do much better when we believe."
"I don't think there was a difference in quality between the two sides," he added. "The game today was about 'who makes the first mistake loses the game'."
Both managers praised new signings.
Wenger described the performance of Belorussian midfielder Alex Hleb as one of a few positives to take from the game, although he has a worry over Swedish midfielder Freddie Ljungberg who left the field on a stretcher after colliding with an advertising hoarding.
"The initial examination showed nothing but he couldn't walk and left the stadium on crutches," said the Frenchman, who will wait for the results of a scan on Monday.
Mourinho said record 38 million euro ($47 million) midfielder Michael Essien, who completed his move only this weekend, showed in the half hour he was on the pitch after replacing Eidur Gudjohnsen "what he can be in the future for us".
"He is more of a pure midfield player than Eidur. He can press and he can give security to the team," Mourinho said.
