Tottenham took the lead thanks to Emmanuel Adebayor, but his subsequent red left them at the mercy of their rivals as Arsenal took full advantage at the Emirates.
The Togolese striker put Tottenham in the lead early as Andre Villas-Boas' brave decision to go to a 4-4-2 formation looked to pay off. Jermain Defoe was allowed to escape down the left by Per Mertesacker, and his shot was saved by Wojciech Szczesny, but Adebayor was on hand to turn in the rebound.
Yet with Spurs looking good, it was all to fall apart a few minutes later as Adebayor went in on Santiago Cazorla with a terrible, studs-up, two-footed challenge. Howard Webb was left with no alternative but to send him off, and Tottenham begin to suffer immediately, Per Mertesacker atoning for his earlier error by venturing forward and getting on the end of Theo Walcott's cross to tie up proceedings.
Tottenham now looked to hold out until half-time. Easier said than done. Lukas Podolski put Arsenal into the lead on 40 minutes with a scrappy finish after the ball bobbled it's way through to him off Tom Huddlestone. But it was to get even worse for Tottenham - perhaps mentally already in the dressing room, Olivier Giroud was allowed to get in between William Gallas and Jan Vertonghen, getting on the end of Cazorla's cross to make it 3-1.
Tottenham responded by changing to a 3-4-1-1 formation, bringing on Clint Dempsey and Michael Dawson for their two fullbacks, Kyle Naughton and Kyle Walker. It had little effect as Arsenal continued bombarding their goal. A man down they may have been, but Spurs allowed it to shock them and put in a poor performance all round, disappointing after their bright start. It was soon duly 4-1 to the Gunners, Santiago Cazorla getting a deserved goal after sweeping home Lukas Podolski's cross as the Tottenham defence disintegrated.
Gareth Bale then pulled a goal back for Tottenham, having to go it alone due to their disorganised midfield and poor passing, running at the Arsenal backline before slamming a shot past Szczesny. There may have been a few nerves that Arsenal would let even a sure thing like this game go, but Tottenham proved unable to put them under any pressure. In the end, Theo Walcott restored the gloss on the scoreline, taking advantage of Spurs giving the ball away to get on the end of Alex Oxlade-Chamberlain's centre.
It would be easy for Tottenham to blame the defeat solely on Adebayor's red card, particularly after their excellent start, but they allowed it to affect them to a great extent - they did not play well even for ten men, and Arsenal could have scored a lot more. They will feel terrible at having potentially kick-started Arsenal's season for the second year in a row, but André Villas-Boas and Spurs fans will have to write this one off to bad fortune with the red card and their absent midfielders. There is still plenty of scope for them to improve - just less and less time.