Hector Bellerin scored an 87th-minute equaliser as ten-man Arsenal twice came from behind to snatch a 2-2 draw at Chelsea, after David Luiz had been sent off on his return to Stamford Bridge.
After Arsenal briefly threatened to assume early control, it was the Blues who created the better initial opportunities.
An Antonio Rudiger header caused Arsenal problems as he headed Callum Hudson-Odoi’s cross into Abraham’s path, but the striker could only plant his own header straight at Bernd Leno from six yards out.
Under minimal pressure, Mustafi, gifted possession to Jorginho and his pass released Abraham in behind Luiz. The Brazilian scrambled as best he could, but as Abraham rounded Leno, Luiz felled him to earn his dismissal.
Jorginho opened the scoring with 28 minutes gone from the penalty spot. However, Arteta was close to introducing Rob Holding before half-time but instead he waited until ten minutes afterwards, and chose Matteo Guendouzi instead, replacing Mesut Ozil.
Yet the Gunners continued to battle and Martinelli took advantage of a fortunate moment to equalise 27 minutes from time for his tenth goal of a promising debut season.
Mustafi headed clear a Chelsea corner and although too many players were caught upfield, Kante had the situation under control as Martinelli overran the ball in the centre-circle.
Yet he slipped with the ball arriving at his feet and Martinelli was suddenly clear, keeping his composure superbly to bear down on Kepa Arrizabalaga and slide a cool finish.
Lampard responded by introducing Ross Barkley and Mount for Kovacic and Kante, but it was Willian and then Abraham who forced Leno into routine saves as Chelsea sought to respond.
Arsenal’s goalkeeper was called upon to make a better stop, as Barkley attempted to glance a header inside his right-hand post. Leno was helpless late on, however, as Hudson-Odoi’s cross was met by Azplicueta in the box and he steered shot into the corner.
Cesar Azpilicueta thought he had won it with an 84th-minute header, however, Hector Bellerin — marking his first appearance since December 5 following a hamstring injury — completed a chaotic end to a thrilling encounter.
He curled home a left-footed effort from the edge of the area to earn Mikel Arteta’s side a valuable point, and dent Chelsea’s hopes of a top-four finish.
Abraham limped off after the match, further deflating Chelsea and their fans. Arsenal remain in tenth place on the table, while Chelsea sit fourth.
Other Premier League results
AFC Bournemouth 3-1 Brighton & Hove Albion
Aston Villa 2-1 Watford
Crystal Palace 0-2 Southampton
Everton 2-2 Newcastle United
Sheffield United 0-1 Manchester City