Eddie Nketiah's 89th minute winner kept Arsenal on course for the Premier League title as they downed Manchester United late on.
The two sides both had to come from behind at different periods as the contest ebbed and flowed in north London, but ended with the Gunners firmly on top. The Red Devils remain the only team to beat the Gunners this term - and threatened to do so again when the in-form Marcus Rashford scored a sublime opener from distance.
Erik ten Hag's celebrations highlighted the importance of the clash, but their lead was short lived as Eddie Nketiah levelled proceedings. Arsenal were able to dominate the midfield and took the lead in the second-half when Bukayo Saka cut-in before scoring in impressive fashion.
The hosts' lead was similarly short-lived as the bandaged Lisandro Martinez scored a clever header in front of the away following to level the contest once more. It looked as if the contest would end level, but Nketiah sent the Emirates in raptures, after a VAR check, as he flicked home late on.
The contest at the Emirates had a whiff of the Sir Alex Ferguson vs Arsene Wenger about it, such is the quality of these two teams, who are once again up at the top. Here are five talking points from north London.
1 A throwback to times gone by
It has probably been well over a decade since an Arsenal vs United clash involved two teams who were in a good moment, ready to compete and at ease with what they are. The contest, with all its history, has always attracted big audiences and been a game to look out for, but it lacked what we had today.
On Sunday it felt like we'd rewound the clock to a time when these two heavyweights were challenging for honours - and that is exactly what they look set to do. Arteta and Ten Hag have created teams that are befitting their club's rich history.
At the Emirates we were treated to a 90 minutes that was full of quality, full of energy and full of optimism for both sides. Arsenal supports will have left the happier, but fans can't have been anything but pleased with what they saw as both outfits showed why they are firmly on the rise.
2 No Jesus, no problem
The Brazilian was the marquee signing at the Emirates in the summer and quickly showed why in the early months of the season. Even when Gabriel Jesus wasn't scoring, he was having a notable affect on the team and the fear was, were he to get injured, Arsenal would drop off.
That fear became a reality at the World Cup, but Nketiah has filled in seamlessly and continues to justify the new contract he penned in the summer. For much of the season he's been Jesus' understudy, but is proving he's more than capable of leading the line for a side with title aspirations.
His header levelled the contest, and showed the predatory instincts he's long been credited with. Jesus is set to be sidelined for several more weeks but his absence is certainly not being felt as Nketiah produced perhaps the moment of the season so far with the winner.
3 Casemiro's absence felt
Ten Hag was keen to remind fans that when United beat Arsenal earlier this season, they did so without Casemiro. Much was made of the Brazilian's absence in north London, which came as a result of his yellow card at Crystal Palace in midweek.
Scott McTominay stepped in to fill the void but he is not a five-time Champions League winner. Casemiro's arrival has galvanised the United midfield, but without him Arsenal exploited and dominated the middle of the park. They were able to play through the visitors, which allowed them to feed their attacking stars.
You imagine, had Casemiro started, that we would've seen a different game, but it was the Gunners who were able to take advantage.
4 Rashford rolls on
You have to remind yourself sometimes that the man wearing the United No 10 shirt is the same man from last season. Rashford was a player bereft of confidence and form and you wondered whether he would get back to the heights he once threatened to reach as a youngster.
Now though, after an impressive pre-season and a new manager giving him instructions, Rashford is leading United's attack. His strike at the Emirates showed bags of quality, but could only have been scored by a man brimming with confidence in his own ability.
His strike was his ninth in all competitions since the end of the World Cup - a tally not bettered by anyone in Europe.
5 Saka joins unique club with moment of class
The young forward was quizzed pre-match on whether he could become the third Arsenal player, after Thierry Henry and Freddie Ljungberg, to score in three successive games against the Red Devils. He said it was "challenged accepted" and he completed it in sensational fashion.
Saka's moment of brilliance was a long-time coming given his first-half display. It also completed the Gunners comeback after they initially trailed. The winger stepped up at the Emirates earlier this season when he scored the winner against and showcased his appetite for the big occasion once more.
