LONDON - Edin Dzeko scored twice as Manchester City heaped more misery on Manchester United with a 3-0 victory to move to within three points of English Premier League leaders Chelsea with two games in hand.
Dzeko needed just 43 seconds to give City the lead on Tuesday at United's Old Trafford ground.
Rafael's last-ditch tackle blocked David Silva's run into the box but Samir Nasri hit the post and Dzeko followed up to sidefoot in the rebound.
The Bosnia striker was on target again in the 56th minute when he dropped marker Rio Ferdinand to volley in Nasri's corner,
Yaya Toure rubbed salt into United's wounds with a third goal in the 90th minute as Manuel Pellegrini's men completed a derby double following a 4-1 win over United at Eastlands in September.
It was yet another night to forget for United boss David Moyes, in his first season in charge of the fading English champions following the retirement of Alex Ferguson, British football's most successful manager.
This result left United 12 points off the top four and effectively needing to win this season's Champions League, where they face holders Bayern Munich in the quarter-finals, in order to qualify for a place among Europe's elite next term.
Arsenal, fresh from the humiliation of being thrashed 6-0 by Chelsea in manager Arsene Wenger's 1000th game in charge last weekend, were held to a 2-2 draw by struggling Swansea at the Emirates Stadium.
Wilfried Bony headed in Neil Taylor's cross to give the Swans an 11th-minute lead in north London.
But two goals in as many minutes midway through the second half turned the match on its head.