Both teams were involved in a fracas just before halftime and Arsenal finished with nine men having had Brazilian defender Gabriel and Spanish midfielder Santi Cazorla sent off.
Gabriel was sent off for what was seen as kicking out at Chelsea striker Diego Costa and although he had his red card rescinded by the FA he still received a one-match ban and a 10,000-pound fine for his protests before leaving the pitch.
Cazorla was sent off after 79 minutes for a second yellow card after a foul on Chelsea's former Arsenal midfielder Cesc Fabregas.
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Costa was handed a three-match ban after the match which Chelsea won 2-0.
Chelsea, meanwhile, announced on Thursday that former Italy and AC Milan goalkeeper Marco Amelia had joined them on a free transfer.
The 33-year-old will provide experienced cover for Asmir Begovic and Thibaut Courtois for the champions who are struggling, fifth from bottom with eight points from eight games.
Belgian international Courtois, the London club's first-choice keeper, will be sidelined until December because of a knee injury.
Amelia, who was released by Milan in the summer of 2014, has signed a contract as a free agent that will keep him at Chelsea until the end of the season.
He had a short-term deal with Serie B side Perugia at the end of last season but never made a first-team appearance.
Chelsea, who have conceded 17 league goals this season, host third from bottom Aston Villa in their next fixture on Oct. 17.
(Writing by Tony Jimenez; Editing by Ed Osmond)
