Arsenal recovered from Erik Lamela's astonishing rabona opener to beat 10-man Tottenham 2-1 in a dramatic north London derby despite the absence of exiled captain Pierre-Emerick Aubameyang on Sunday.
Lamela scored one of the greatest goals in Premier League history with an audacious strike in the first half at the Emirates Stadium.
But the Tottenham forward went from hero to villain when he was sent off for a second booking after Jose Mourinho's side blew the lead.
Martin Odegaard had equalised with a deflected effort just before half-time and Alexandre Lacazette sealed the points with a second half penalty.
Lamela's moment of genius was ruined by his red card and it was Arsenal's day as they beat Tottenham for the first time in six games.
Denting Tottenham's bid to qualify for the Champions League via a top four finish in the Premier League was an added bonus for Arsenal, who hadn't defeated their neighbours since 2018.
It was an even more impressive success given Arsenal manager Mikel Arteta caused a storm by dropping Aubameyang as punishment after he reportedly turned up late for a pre-match team meeting.
It is believed Arteta had grown frustrated with Aubameyang for similar offences in the past.
"He was going to start the game, but we had a disciplinary issue. We've drawn the line. We keep it internal," Arteta said before leaving Aubameyang as an unused substitute for the entire match.
After just a third loss against the Gunners in Mourinho's career, Tottenham remain without a win at Arsenal since 2010 and are six points adrift of fourth-placed Chelsea, with Arteta's team a further four points behind.
All eyes were on Aubameyang when the teams emerged before kick-off and the 31-year-old sat behind the Arsenal bench with his black face mask only partially disguising his gloomy expression.
Arsenal ignored the Aubameyang drama and Emile Smith Rowe whipped a dipping long-range strike over Hugo Lloris and onto the crossbar in the early stages.
Tottenham suffered a blow when Son Heung-min was replaced by Lamela in the 19th minute after the South Korea forward pulled up sharply while chasing a long pass.
After being out-played for the first 33 minutes, Tottenham took the lead in outrageous style with their only shot of the half.
When Lucas Moura found Lamela in the penalty area, the Argentine flicked his back foot behind his standing front leg to guide an audacious finish through Thomas Partey's legs and past Bernd Leno into the far corner.
"This is one of the best goals I've ever seen in the Premier League. We've never seen anything like this," former Tottenham midfielder Jamie Redknapp told Sky Sports.
The 29-year-old's impudent effort recalled a similar goal he unleashed against Asteras Tripolis in the Europa League in 2014.
Lamela's first league goal this season could have shattered Arsenal's fragile morale but they hit back strongly.
Cedric fired against the post before the Gunners got a stroke of luck with their 44th minute equaliser.
Kieran Tierney's cross reached Odegaard 12 yards out and the on-loan Real Madrid midfielder swivelled for a low shot that deflected off Tottenham's Toby Alderweireld as it beat the wrong-footed Lloris.
With Tottenham lacking momentum, Mourinho hauled off Gareth Bale early in the second half to the obvious irritation of the Wales forward.
But Arsenal remained on top and they took the lead in the 64th minute.
Nicolas Pepe's pass gave Lacazette a sight of goal and Davinson Sanchez made a despairing lunge that clattered into the French striker.
Michael Oliver pointed to the spot and Lacazette picked himself up to slot home the penalty.
Lamela saw red in the 76th minute after crashing his arm into Tierney's face.
Tottenham laid seige to Lloris's goal, but Harry Kane's header was erased by an offside flag before the striker hit a post with his free-kick in the final moments.
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