Arsenal staged a stunning late fightback to earn a point at Stamford Bridge just as Chelsea looked about to enjoy their finest victory under manager Mauricio Pochettino.
Victory means Chelsea remain unbeaten since Guus Hiddink replaced Jose Mourinho and they have not lost in their last nine league meetings with Arsenal, who are third, three points behind leaders Leicester City.
Olivier Giroud scored with a neat low header to hand Chelsea the lead against Arsenal in Baku. Soon after, Pedro swept home to double Chelsea's lead after clever work by Eden Hazard.
Cesc Fabregas says he decided to join Chelsea after Arsenal failed to contact him when he became available for transfer at Barcelona. "I feel very attached, even now, to Arsenal," he told Sky Sports.
Arsenal have agreed a deal to sign Chelsea defender David Luiz for a fee of around £8million. The Brazilian refused to train on Thursday as he looked to force through a shock move to the Emirates.
One Chelsea fan replied: "Make him Chelsea captain immediately." Another said: "My future captain." One wrote: "Finished Arsenal." Another added: "We love you Reece, propa Chels."