Arsenal came from behind to beat 10-man Tottenham in a heated north London derby as the Gunners moved ahead of their neighbours and into the Premier League top-four.
A fiery atmosphere inside the Emirates Stadium was echoed on the pitch as quickfire goals from Alexandre Lacazette and Lucas Torreira settled the contest 4-2 in favour of the hosts.
Pierre-Emerick Aubameyang had given Arsenal the lead from the penalty spot before drawing them level after an Eric Dier header and a controversial Harry Kane spot-kick had turned the game around.
Tottenham defender Jan Vertonghen, having conceded the first penalty, was dismissed in the latter stages after picking up a second booking for a foul on Lacazette.
There were a number of minor flashpoints, with the biggest furore following Dier's equaliser, as Unai Emery got the better of his close friend Mauricio Pochettino to take Arsenal up to fourth - ahead of Spurs on goal difference - and extend their unbeaten run to 19 matches in all competitions.
Spurs have had the best of this fixture in recent seasons, this was only Arsenal's second derby win in their last nine attempts, but the hosts were good value for their victory over a frenetic 90 minutes.
Going against recent trends, Arsenal were quick out of the blocks and had Tottenham rattled as they chased and harried.
The hosts were duly rewarded as referee Mike Dean pointed to the spot with nine minutes gone, the official doing well to spot Vertonghen's handball as he pushed the ball away from the head of Shkodran Mustafi.
Aubameyang stepped up to coolly convert the resulting penalty, his ninth Premier League goal of the season.
Aubameyang had a great chance to double his tally for the afternoon but fluffed his lines as Sead Kolasinac's deflected cross found him six yards out.
Emery's side continue to impress, a quick-thinking Granit Xhaka flashing a free-kick into Kolasinac who burst past the struggling Serge Aurier to provide a cross which saw Alex Iwobi draw a smart low save out of Hugo Lloris.
The Tottenham equaliser came from a free-kick as Dier flicked Eriksen's near-post set-piece past Bernd Leno, who should have kept the effort out.
Tempers flared on the touchline as Dier celebrated in front of the home fans and Arsenal's substitutes, with Stephan Lichtsteiner taking particular offence to the England midfielder holding his finger to his lips.
Pochettino charged down the touchline to control his players but the goal lifted Tottenham and moments later they hit the front as Dean again pointed to the spot.
This time the decision was more controversial as Rob Holding was penalised for sliding in and tripping Son, who appeared to go down with little to no contact.
Kane stepped up slammed home the penalty, sending Leno the wrong way and putting Tottenham ahead.
Arsenal reacted well and were almost level on the stroke of half-time as Mustafi's looping header came back off the crossbar.
Emery made two changes at half-time as Lacazette and Aaron Ramsey replaced Iwobi and Henrikh Mkhitaryan and both played their part in turning the game around.
Hector Bellerin's perfectly-weighted pass found Ramsey, who touched the ball into the path of Gabon international Aubameyang and he arrowed his strike past a helpless Lloris.
The strike reinvigorated Arsenal and they were so close to reclaiming the lead on the hour-mark.
Holding headed a corner down to Mustafi, whose strike was cleared off the line by Dele Alli as Torreira fired the rebound wide.
Bellerin almost gifted Tottenham a third, passing the ball across goal straight to Son, who could not beat Leno with the resulting strike.
But it would be Arsenal who celebrated the fifth goal of a memorable game as Juan Foyth dawdled in possession and was robbed by Ramsey - who found Lacazette and his effort was deflected past Lloris courtesy of a big deflection off Dier.
The points were secured when Torreira tucked away his first goal for Arsenal after Aubameyang slipped him in with a fine pass, before Vertonghen saw red for following through on Lacazette.