Goals from Alexandre Lacazette, Granit Xhaka and Bukayo Saka sealed a deserved win for a young Gunners side, with Frank Lampard’s Premier League title contenders turning in a deeply disappointing performance at the Emirates.
With Arteta heading into the game having lost Brazilian trio Gabriel Magalhaes (self-isolation), David Luiz and Willian (both ill), the Gunners manager opted to hand youngster Emile Smith Rowe a big chance in a creative role with Gabriel Martinelli in front of him.
A young Gunners side repaid Arteta’s faith with a superb opening 45 minutes, and were well worth their two-goal lead at the interval.
Chelsea started the second half with a renewed vigour, but the next goal was always going to be crucial – and it went to the hosts as Saka’s cross from the right of the box floated over Mendy and into the top corner.
Tammy Abraham added a late consolation goal for Chelsea following a lengthy VAR review for offside.
Chelsea threatened a late comeback as Mason Mount won a penalty off Pablo Mari, but Bernd Leno saves well from substitute Jorginho to make the victory secure.
The win is a huge boost for Arteta following a string of poor results in recent months, while a 3-0 reverse will set alarm bells ringing at Stamford Bridge given the nature of the performance.