Gabriel Magalhaes scored the only goal of the game as Arsenal returned to the top of the Premier League with a derby win at Chelsea
Gabriel capitalised on some terrible Blues defending from a Bukayo Saka corner in the second half to move Mikel Arteta's side two points clear of Manchester City.
The Gunners were good value for their third consecutive away win over their London rivals in the top flight, as Pierre-Emerick Aubameyang endured a miserable first game against his former club.
Chelsea have now suffered back-to-back top-flight defeats and this was their first loss at Stamford Bridge since going down 4-2 to Arsenal in April.
Arsenal dominated possession in a bright start and Ben White spurned a chance to put them in front when he dragged a shot wide from the edge of the penalty area.
Aubameyang was booed by the Gunners fans and the striker's only notable contribution in the first half was when he was booked for a late challenge on White.
Gabriel Jesus wasted a glorious chance to open the scoring just before the half-hour mark, ending a brilliant sweeping move by somehow heading Gabriel Martinelli's cross wide from close range.
Arsenal failed to have an attempt on target in the first half and they were wasteful again 10 minutes after the break, when Thomas Partey nodded wide with Martinelli behind him poised to head home Martin Odegaard's delivery.
There was more frustration from Jesus when he was denied from a tight angle, but Mikel Arteta's side were deservedly in front after 63 minutes as Chelsea were caught napping.
Gabriel could not believe his luck when Saka's corner evaded everyone and gave him a tap-in to break the deadlock.
Odegaard sliced a poor finish off target after great work Jesus, but Gabriel’s goal secured three precious points.
What does it mean? Gunners make another statement
While there was only one goal in it, Arsenal were much the better side and Chelsea never really looked like scoring in a lacklustre display from Graham Potter's side.
Rock solid at the back and showing great intensity from the start, the Gunners gave another demonstration of their title credentials with a third win in a row Stamford Bridge for the first time since 1974.
As they sit pretty on top of the table, Chelsea are down in seventh after a 12-match unbeaten home run came to a halt.
A stroll for classy Saliba
His central defensive partner Gabriel popped up for the winner, but William Saliba was outstanding at the heart of an Arsenal back four that also included a fit-again Oleksandr Zinchenko.
Saliba has been a revelation under Arteta this season and he did not appear to break sweat, reading the game like a book with superb positional play as he gained possession 13 times and did not put a foot wrong.
Arsenal supporters must have been fearing their ex-captain Aubameyang would return to haunt them, but he only had eight touches before being replaced by Armando Broja just after Gabriel's goal.
He only had one shot and was cautioned as his frustration got the better of him.
Key Opta Facts
- Arsenal are the first side to win 10 Premier League away games against Chelsea, while they are just the second visiting side to win three in a row at Stamford Bridge after Blackburn Rovers (1993-94 to 1995-96).
- Arsenal have won three consecutive Premier League games against 'big six' opponents for the first time since April 2012.
- The Gunners remain the only side to have scored in every Premier League game so far this season, while no side has kept more clean sheets (6).
- Chelsea have lost consecutive Premier League games for the first time since December 2020, under Frank Lampard.
Chelsea travel to Manchester City for an EFL Cup clash on Wednesday, when Arsenal head south to face Brighton and Hove Albion in the third round.