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 is an incredible guy and one of the most important players in the team. He is our captain and these things happen," Arteta said after leaving Aubameyang as an unused substitute for the entire match.
"We have lots going on in our lives and people finding it hard with the restrictions. I will never tell anything that happens in the dressing room.
"I love the reaction of the team. We stayed composed and in the end we won the game."
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.
Mourinho was furious with the penalty decision, saying: "We played really bad in the first half. No intensity or pressing. Some important players hiding. But no post-match interviews for referees? That is a pity.
"My record with Michael Oliver on penalties with Chelsea, United and Tottenham is unlucky.
"I did not complain but when I watch back on the iPad it is what it is. If somebody has a different opinion it has to be one of the big Arsenal fans with a season ticket."
All eyes were on Aubameyang when the teams emerged before kick-off.
The 31-year-old sat behind the bench with his black face mask only partially disguising his gloomy expression, but Arsenal ignored the drama.
- Derby drama -
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.
Arsenal hit back strongly with their 44th minute equaliser.
Kieran Tierney's cross reached Odegaard 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 Hugo Lloris.
Arteta's men took the lead in the 64th minute when 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 hit a post with his free-kick in the final moments.