Arsenal 2 Chelsea 2: Hector Bellerin scores in 92nd minute to seal draw in Emirates thriller
The two sides shared an incredible 33 chances, with the heroic keeping of Gunners' Petr Cech and Blues' Thibaut Courtois ensuring only four goals were conceded.
Courtois had made exceptional stops to deny Alexis Sanchez and Alexandre Lacazette before he was finally beaten when Jack Wilshere fired high past him in the 63rd minute.
The lead only lasted four minutes, Eden Hazard converting from the spot to level after his foot had been caught by Bellerin.
Arsenal manager Arsene Wenger labelled Anthony Taylor's decision "farcical", adding "you could give 10 penalties like that a game".
Chelsea must have thought they had secured all three points when Marcos Alonso flicked home substitute Davide Zappacosta's low cross after 84 minutes.
But in the second minute of stoppage time, Bellerin produced an exceptional half-volley to earn the Gunners a point.
There was more drama seconds from the end when Zappacosta's shot thundered off Cech's crossbar.
Man of the match - Eden Hazard (Chelsea)
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What's next?
Arsenal are at Championship club Nottingham Forest in the third round of the FA Cup on Sunday (16:00 GMT) and face Chelsea again in the Carabao Cup semi-final first leg next Wednesday (20:00 GMT). Before that match Chelsea are at Norwich's Carrow Road on Saturday (17:30 GMT) for their FA Cup tie.
