Two controversial goals secure comfortable win for Arsenal over rivals Tottenham
Arsenal proved they are still a force to be reckoned with by blowing away Tottenham in a pulsating north London derby.
Spurs had been hailed as the dominant force in this fiercest of rivalries but goals from Shkodran Mustafi and Alexis Sanchez secured the Gunners a dominant 2-0 victory at the Emirates Stadium.
The result means Arsenal move just one point behind Tottenham.
There was a hint of fortune about each of Arsenal's first-half goals. Mustafi's header came after referee Mike Dean had awarded a dubious free-kick for a foul on Sanchez while Alexandre Lacazette was just offside in the build-up to their second.
But few could argue with the result as Arsene Wenger's side beat Tottenham at their own game, showing themselves faster, stronger and hungrier than their opponents in every department.
If Arsenal could produce this sort of ruthless performance more consistently, they would surely be title contenders.
Harry Kane wore a bandage around his right knee but he and Dele Alli, who both pulled out of England duty last week, were deemed fit enough to start although Harry Winks dropped to the bench. Hugo Lloris shook off a groin strain and Danny Rose was a curious omission from the squad.
For Arsenal, Lacazette was handed a starting spot up front but Jack Wilshere and Alex Iwobi were only among the substitutes.
Arsenal were all over Spurs from the outset, with Eric Dier's pass out under pressure falling straight to Sanchez but Lacazette fired over.
It was a warning of what was to come and while a mix-up between Mustafi and Laurent Koscielny allowed Kane a rare sight of goal, Arsenal were soon pulverising their opponents with wave after wave of attack.
Ben Davies seemed a particular target, with several openings coming down Tottenham's left, as Hector Bellerin and Mesut Ozil both fired dangerous balls across the box.
It was no more comfortable for Davinson Sanchez on the opposite flank as he was harried into playing a limp back-pass to Lloris, who just scrambled away ahead of the chasing Lacazette.
Christian Eriksen, virtually anonymous until this point, clipped the post with a dragged shot but it was no surprise when Mustafi headed Arsenal in front in the 36th minute.
Arsenal were fortunate to win the free-kick for the slightest of shirt-pulls from Davinson Sanchez on Alexis Sanchez before Mustafi climbed above the rooted Jan Vertonghen to head in at the far post.
Tottenham were rattled but five minutes later they were two down. Lacazette nipped in between Vertonghen and Davies, squared to Sanchez, who bundled in at the near post.
Lacazette's arm looked on replay to have just been offside and Spurs assistant Jesus Perez waited to give Dean an earful in the tunnel at half-time.
The visitors could hardly argue with the scoreline, however, although they came out with renewed impetus after the break. Kane wanted a penalty for Sead Kolasinac cutting across him and seconds later drew a last-ditch block from Mustafi.
But while Arsenal dropped deeper, content to allow their opponents more possession, Tottenham struggled to find a breakthrough.
Wenger's decision to take off Lacazette was greeted by boos. However Pochettino hauling off both Kane and Alli prompted celebrations from the home support.
Dier's header drew an acrobatic save from Petr Cech and substitute Son Heung-min could have created a nervy finish if he had done better with two half-volleys late on.
As it was, Arsenal played out a surprisingly comfortable victory.