Thomas Vermaelen headed Arsenal into third place in the Premier League for the first time this season after a hard-fought 1-0 win at Everton on Wednesday.
Arsenal, who have now won six top-flight games in a row, leapfrogged Tottenham after Belgium defender Vermaelen struck in the eighth minute, while their north London rivals were held to a 1-1 draw by Stoke.
It was hardly vintage Arsenal and Everton will be upset Royston Drenthe's 'equaliser' was ruled out by a controversial off-side flag.
But having trailed Tottenham for most of the season, Arsene Wenger's men have opened up a one-point cushion over their neighbours.
Arsenal had come from behind to secure victory in their previous four league outings but they didn't need to this time after Everton gifted their opponents an early lead.
Robin van Persie is used to scoring goals rather than teeing them up, but the Netherlands striker's corner allowed Vermaelen to power a header beyond United States keeper Tim Howard after out-jumping the home defence.
Everton, sluggish throughout the first half, could not say they had not been warned.
Two minutes earlier van Persie headed into the path of Aaron Ramsey, the 21-year-old Wales midfielder screwing his volley horribly wide from a good position.
Arsenal, back in action after a nine-day break, were everything Everton were not in the early stages -- hungry, determined and eager to wrap up victory before half-time.
Tony Hibbert made a vital block to deflect Ramsey's goal-bound effort out for the corner from which Vermaelen broke the deadlock before Howard made a crucial save to stop van Persie making it 2-0 in the 10th minute.
Vermaelen might have been the goal hero but Arsenal's travelling fans in the Goodison crowd of 30,330 were only interested in chanting the name of one player.
"Fabrice Muamba, we're Thinking Of You" they sang in praise of their former player, who collapsed from the cardiac arrest he suffered during Bolton's FA Cup quarter-final with Tottenham last Saturday.
Arsenal included Mikel Arteta in their side, the Spanish playmaker making his first return to Goodison Park since making a £10 million move from Everton at the end of last August.
But Arteta was fairly anonymous on his Merseyside return as Everton came back into the game.
Drenthe was controversially denied a 32nd-minute equaliser by an offside flag, while Nikica Jelavic headed straight at Arsenal keeper Wojciech Szczesny in the early stage of the second half.
Yet only the woodwork saved Everton from falling 2-0 behind after van Persie let fly when Kieran Gibbs nodded the ball into his path.
Everton had won their previous three top-flight home games against Manchester City, Chelsea and Tottenham.
But their hopes of defeating Arsenal for the first time since March 2007 vanished when Szczesny produced a fine save to deny Marouane Fellaini after he had burst into the Gunners penalty area.
In an exciting finale, Howard made an excellent late save to keep out Tomas Rosicky's fierce effort from close range as Arsenal finished strongly.