LONDON -- Three years after leaving Arsenal, Emmanuel Adebayor again played a key role in helping Arsene Wenger's side win the north London derby.
After putting Tottenham in front in the 10th minute on Saturday, the striker handed the initiative to his former team eight minutes later when he was sent off for a high challenge on Santi Cazorla.
Arsenal made the most of its numerical advantage, replicating its 5-2 derby win at the Emirates Stadium in February to rise above Tottenham into sixth place.
"The sending off of Adebayor ... certainly changed the game because Adebayor had a good start -- he was lively," said Arsenal manager Arsene Wenger, who sold Adebayor to Manchester City in 2009.
Per Mertesacker started Arsenal's comeback with a 24th-minute header, and Lukas Podolski and Olivier Giroud both found the net before halftime.
Cazorla swept in the fourth goal on the hour before Gareth Bale reduced the deficit for Tottenham, but Theo Walcott knocked in the fifth in stoppage time to give Arsenal a lift after its worst start to a season since during Wenger's 16-year reign.
"If we show that courage and ambition every game we will climb up the table," Walcott said. "We showed people how good we are today ... it will give us tremendous spirit."
Despite a third successive league loss, Tottenham manager Andre Villas-Boas said he was proud of his players.
"We were very good from the first minute to the last," he said. "The feeling of the result is indifferent for us when we played so well and took the risk in the second half to be so bold in the second half playing three at the back.
"I don't think (the sending off) changed the running of the game. We looked in control apart from the 10 minutes before half time."
It had been a bright start with Tottenham's former Arsenal players William Gallas and Adebayor both finding the net.
Gallas' goal was ruled out for offside but a minute later there was no disputing Adebayor's effort.
Jermain Defoe latched onto Jan Vertonghen's deep ball, cut in from the right and his shot was parried by Wojciech Szczesny, who was returning from a two-month layoff.
But Adebayor, who scored four goals for Arsenal against Tottenham in the 2008-09 season, was on hand to nudge the loose ball over the line.
With their lead, Spurs upped the pressure and Aaron Lennon came close to doubling the advantage, but his shot crept round the post.
And the match swung in Arsenal's favour when Adebayor launched his high challenge at Cazorla, completely missing the ball and hitting the midfielder's right ankle.
Referee Howard Webb showed Adebayor a straight red card on just his second start of the league season and, as tensions increased, Arsenal midfielder Jack Wilshere and Bale were also involved in an altercation.
"There was no intention to do any harm," Villas-Boas said. "I think the sending-off determined the game, but the referee made the right decision."
With its numerical advantage, Arsenal drew level in the 24th minute as Walcott went past Kyle Naughton and whipped in the cross that Mertesacker met with a powerful header.
Arsenal was now in in command, with a couple of dangerous headers coming from Giroud, although acrobatic goalkeeper Hugo Lloris did well to block them both after he dislodged Brad Friedel from a Tottenham league lineup for the first time since Oct. 7.
Arsenal, though, went in front in the 42nd when Wilshere slotted the ball through to Podolski and the Germany striker's scuffed shot deflected off Gallas into the net.
And in first-half stoppage time, Cazorla stayed on his feet after being fouled, regained his composure and went out to the left. From there, he crossed to Giroud, who swept the ball into the net.
Trailing 3-1, Tottenham manager Andre Villa-Boas at halftime took off two of the back four, Naughton and Kyle Walker, and brought on defender Michael Dawson and striker Clint Dempsey.
It didn't make much of a difference, although Cazorla took until the hour-mark to score Arsenal's fourth. The Spaniard netted at the far post after connecting with Podolski's cross.
But Arsenal switched off at the back, allowing Bale to rampage through before knocking the ball past Szczesny with his weaker right foot to give Spurs a brief hope of a comeback.
It wasn't to be.
The three-goal cushion was restored in stoppage time when Alex Oxlade-Chamberlain charged down the right and crossed to Walcott, who controlled the ball before striking past Lloris.