By Chris Harris at White Hart Lane
Arsenal lost for the first time in six games as Tottenham came from behind to win the north London derby.
Mesut Ozil volleyed the visitors ahead in the 11th minute following good work from Danny Welbeck, but Harry Kane tucked home a second-half equaliser from close range.
David Ospina made a string of important saves as Tottenham enjoyed long spells of pressure, but Kane beat the Colombian with a towering header four minutes from time.
Welbeck and Laurent Koscielny went closest to a second goal for Arsene Wenger's side, but Spurs goalkeeper Hugo Lloris kept them at bay.
Like any derby defeat this one is hard to swallow, but Arsenal were not at their best at White Hart Lane.
They have an early chance to get back on track when Leicester City visit Emirates Stadium on Tuesday.
SETTING THE SCENE
Wenger's 45th derby was also his 700th Premier League game as Arsenal manager - and he sprang a minor surprise before kick-off.
Welbeck, back after six weeks out with a thigh injury, replaced Theo Walcott in an otherwise unchanged line-up. Calum Chambers dropped out of the squad while Tomas Rosicky - the matchwinner in this fixture last season - was among the substitutes.
Arsenal went into the game on the back of five straight wins, yet mindful that they hadn't registered back-to-back away wins in the Premier League for more than a year.
White Hart Lane would be the perfect place to change that, but Tottenham were on a good run of their own - and in Kane, they had one of the top flight's in-form strikers.
As ever, derby day brought with it extra tension as the red and white halves of north London locked horns. This was about more than Premier League points - local pride was at stake.
Arsenal were ahead inside two minutes on their last visit to White Hart Lane. This time they had to wait an extra nine minutes to take the lead.
Ozil was the scorer but the goal owed so much to Welbeck, who justified his inclusion with a burst beyond Rose on Arsenal's right. He found Olivier Giroud and the Frenchman's mis-hit shot was volleyed past Lloris by Ozil - it was the German's third goal in three games.
As with last season, the game's pattern was set: Tottenham pushing on, Arsenal trying to stay compact before breaking at pace.
Kane underlined his threat with a curling effort which Ospina tipped around the post at full stretch. But the biggest threat to Arsenal's first-half advantage came from a more unlikely source - Rose.
The Spurs full back has previous in local derbies - he scored an outrageous volley here in 2010 - and he gave Bellerin a thorough examination on Arsenal's right.
One shot from Rose was well saved by Ospina, and he went even closer with a fizzing low effort that beat Ospina and flew half a yard beyond the far post.
The likes of Santi Cazorla, Aaron Ramsey and Ozil all had to stifle their attacking instincts as Spurs pushed Arsenal back, but Ozil did lead a couple of dangerous breakaways.
But most of the pressure was coming from Spurs. Lamela robbed Cazorla on the edge of the box and forced another fine save from Ospina, and the same player swiped another effort over before the break.
Arsenal alleviated the pressure with a spell of possession early in the second half, and Cazorla drew a sprawling save from Lloris after Bellerin's cross was half-cleared.
But the visitors were pegged back 11 minutes after the restart.
A near-post flick-on from Eric Dier was tipped away by Ospina, but the ball dropped invitingly for Kane just beyond the far post and he slammed home the equaliser.
Suddenly it was all Tottenham. Arsenal's defenders were at full stretch to clear their lines as Rose and Kane both tried their luck, then Mousa Dembele forced yet another stop from Ospina.
As the hour mark ticked by, the smart money was on a goal for the home side, but Arsenal suddenly came out of their shells.
Welbeck was the catalyst with a brilliant curling effort that Lloris flew across goal to keep out. Then Laurent Koscielny powered a free header at the Spurs keeper from the resulting corner. A couple of yards either side and Arsenal would have led.
Back came Tottenham. Coquelin, industrious as ever in front of the back four, headed away an effort from Dier, and Mason's volley was held by Ospina.
Wenger brought on Rosicky and then Walcott in an attempt to win the game, and the pendulum did swing Arsenal's way for a while.
But Kane had the final word, meeting Nabil Bentaleb's cross with a towering header beyond Ospina.
Referee: Martin Atkinson
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