Kyle Walker's first goal for Tottenham sealed a 2-1 victory for Harry Redknapp's side over their north London rivals Arsenal at White Hart Lane on Sunday.
Walker caught out Arsenal goalkeeper Wojciech Szczesny with a 30-yard strike in the second half after Aaron Ramsey had cancelled out Tottenham midfielder Rafael van Der Vaart's first half opener.
The result means Tottenham move up to sixth place, five points ahead of their hated neighbours after a derby victory that brought an abrupt end to Arsenal's recent revival.
This was the Gunners' fourth defeat in seven Premier League games and they are 15th in the table, just two points off the relegation zone.
Arsenal boss Arsene Wenger's frustration was evident in a fractious exchange with Clive Allen, the Tottenham coach, on his way down the tunnel after the final whistle.
The visitors had appeared capable of claiming at least a point until Walker drilled in a powerful long range shot that found its way through the arms of Szczesny, summing up the Gunners' difficult start to the campaign.
Wenger marked the 15th anniversary of his appointment as manager two days before this game by praising his side's spirit and mental strength after three successive victories over Shrewsbury, Bolton and Olympiakos.
But that run was always under threat against an in-form Spurs side inspired by former Arsenal striker Emmanuel Adebayor.
Spurs had started the game brightly and should have gone ahead in the seventh minute when Van der Vaart released Scott Parker into the visiting area only for the midfielder to place his shot too close to keeper Szczesny.
Arsenal responded with a left shot from Theo Walcott that Spurs keeper Brad Friedel tipped wide of the post.
And when Van der Vaart failed to convert a good opportunity at the near post midway through the half, Wenger's side again reacted well, this time through Robin van Persie, who created a clear opportunity with a clever pull back that was wasted when Gervinho connected with a tame shot wide.
Arsenal were looking nervy in front of goal and when Gareth Bale sent a powerful shot narrowly over at the start of the second half, Tottenham showed signs of taking control of the game.
Both sides had chances to score but it took the combination of Adebayor and Van der Vaart to conjure the opener.
Adebayor's chipped pass found his team mate in space on the edge of the Arsenal area and the Holland striker brought the ball under control and finished with a left foot shot.
Arsenal centre back Per Mertesacker immediately appealed for handball but referee Mike Dean adjudged that Van der Vaart had collected the ball on his chest although television replays suggested the decision was marginal.
The Gunners matched the hosts chance for chance and this time were rewarded for their efforts when Ramsey struck six minutes into the second half.
The opening came after Younes Kaboul had only half cleared an Arsenal corner and Alex Song was allowed to run to the byline and deliver a low cross that the Wales captain turned home from close range.
Now Arsenal were in the ascendancy and Redknapp's growing concern was reflected in his decision to introduce Sandro to shore up his midfield in place of Van der Vaart.
The switch helped steady the home side, although Redknapp could hardly claim that Walker's 73rd minute strike was the result of a tactical masterplan.
The full back chanced his arm after Luka Modric's attempted shot had been deflected back towards the halfway line, advancing to within 30 yards of goal before unleashing a powerful drive that Szczesny should have kept out.