Controversial goals from Shkodran Mustafi and Alexis Sanchez gave Arsenal their first Premier League success against Tottenham for over three years as the Gunners won 2-0 in a heated north London derby on Saturday.
Arsene Wenger's side ended a six-match winless run against their hated rivals thanks to a pair of fiercely debated first-half goals at the Emirates Stadium.
Tottenham were furious that referee Mike Dean awarded a free-kick for Davinson Sanchez's challenge on Alexis Sanchez and their indignation grew louder when, from the resulting set-piece, Mustafi headed Arsenal's opener from what the visitors claimed was an offside position.
Mauricio Pochettino's men felt hard done by again when Sanchez doubled Arsenal's lead by converting a pass from Alexandre Lacazette, who looked offside in the build-up to the goal.
Arsenal's first league win over Tottenham since March 2014 was a welcome tonic after their chastening loss at leaders Manchester City before the international break.
Arsenal move within one point of Tottenham and, even if City remain a distant speck on the horizon, proving the balance of power in north London hasn't completely shifted to their neighbours was cause enough for jubilation among Gunners fans.
Having finished above Arsenal for the first time in 22 years last season, Tottenham missed a chance to underline their ascendency and remain without a win at the Emirates since 2010.
It was a major blow to their title hopes and Pochettino must be concerned that Harry Kane and Dele Alli looked rusty after missing England's friendlies due to injury.
When Kane wasted his only decent chance in the opening moments -- firing too close to Arsenal goalkeeper Petr Cech -- it was a sign of the angst to come for Tottenham.
Despite a largely frustrating time in 2017, Arsenal remain a potent force on home turf, where they have now won their last 11 league games.
Driven on by the effervescent Sanchez, they had no trouble turning the screw on Tottenham and almost took the lead when Aaron Ramsey's exquisite pass caught Tottenham left-back Ben Davies out of position.
Gunners defender Hector Bellerin met Ramsey's ball and whipped over a cross that narrowly eluded the lunging Lacazette in the six-yard box.
Lacking the hunger that inspired their famous win over European champions Real Madrid, Tottenham had reverted to the diffident mood that has often marred their trips to top-six rivals since Pochettino took charge.
Against the run of play, Christian Eriksen could have put Tottenham ahead when his low shot clipped the outside of a post.
But the momentum remained with Arsenal and the dam broke at last as they opened the scoring in the 36th minute.
When Sanchez was harshly penalised by Dean for a challenge on his Arsenal namesake, Mesut Ozil lofted a free-kick towards Mustafi, who got in front of Jan Vertonghen to loop a header past Hugo Lloris into the far corner.
If Tottenham felt injustice over that one, there was worse to come five minutes later.
Bellerin's pass found Lacazette playing on the shoulder of the Spurs defence and, when the offside flagged stayed down again, he raced away and picked out Sanchez.
The Chile forward took a touch before smashing his shot into the roof of the net from close range for only his third Arsenal goal this season.
Pochettino's assistant Jesus Perez was furious with Dean as he stormed down the tunnel at half-time, but in truth Tottenham had only themselves to blame for allowing Arsenal to seize the initiative.
Although Tottenham played with more purpose after the interval, their luck was out as Kane's goal-bound effort was blocked by Mustafi.
Sanchez almost made it three when his strike was repelled by Lloris and Cech's fine save from Eric Dier's header ensured there would be no late Tottenham revival.