A superb 30-metre swerving drive by Michael Essien four minutes from time snatched Chelsea a 1-1 draw with Arsenal and spared the champions their first home defeat for more than two years on Sunday.
Chelsea had struggled to impose themselves on their London rivals and fell behind to a shot by Mathieu Flamini in the 78th minute.
Chelsea, who last lost at home in the league in February 2004 - against Arsenal - roared back and earned their point with a thunderous drive by Ghana midfielder Essien.
They also hit the bar from point-blank range in injury time, with Frank Lampard also hitting a post at the death.
The result leaves Chelsea eight points behind Manchester United, who beat Manchester City 3-1 on Saturday, although the champions do have a game in hand.