Wayne Rooney’s sensational 77th-minute overhead kick gave Manchester United the derby spoils against City at Old Trafford.
The Blues had the better of the game but trailed to Nani’s first-half opener, although David Silva’s freakish goal - Edin Dzeko’s drive deflecting in off the Spaniard as he turned his back - looked as though it would get them at least a point.
But Rooney met Nani’s cross with a staggering effort to leave United eight points ahead of their local rivals with a match in hand.
Title rivals Arsenal saw off Wolves 2-0 as Robin van Persie’s brace took his tally to nine goals in five Barclays Premier League games.
The Dutchman’s superb off-balance volley with his weaker right foot opened the scoring and Richard Stearman’s goal-line clearance denied Cesc Fabregas before Van Persie doubled the lead (56), lashing home after being set up by Theo Walcott.
At the other end of the table, West Ham had further reason to celebrate following this week’s Olympic Stadium vote as they came from 3-0 down to draw 3-3 with West Brom.
Albion led inside three minutes as Graham Dorrans let fly from almost 25 yards to score his first goal of the season, and winger Jerome Thomas stroked home five minutes later after being teed up by Marc-Antoine Fortune.
A harsh offside flag deprived Carlton Cole of a goal to cut the deficit, but it was 3-0 when Dorrans’ left-wing free-kick was diverted into the net by the arm of Hammers defender Winston Reid.
West Ham’s Gary O’Neil hit the crossbar from long range and Demba Ba pulled a goal back five minutes after half-time, his first in English football, after being brilliantly picked out by Mark Noble.
Noble’s free-kick and Frederic Piquionne’s header created the second for Carlton Cole (58) and Piquionne headed against the bar before Ba completed the fightback, volleying home Noble’s deflected cross following a short corner.
Blackpool ended their five-match losing run with a 1-1 draw against Aston Villa.
Gabriel Agbonlahor gave Villa a 10th-minute lead as Darren Bent’s flick put him clear and he rounded goalkeeper Richard Kingson before rolling the ball home as two defenders scrambled back.
But Elliot Grandin quickly equalised, nodding in Charlie Adam’s corner at the near post. Villa lost Jean Makoun to a red card in the second half after a two-footed challenge on DJ Campbell.
Liverpool were forced to settle for a draw after leading at home to Wigan, Raul Meireles volleying them in front following James McCarthy’s error (24) before Luis Suarez hit the post.
But Steve Gohouri poked home a close-range equaliser as Liverpool failed to defend Charles N’Zogbia’s cross before Suarez was denied by the woodwork for a second time, his free-kick clanging back off the crossbar.
Nikola Zigic’s header deep in injury-time earned Birmingham a 1-0 win over Stoke, the giant Serbian heading home after excellent work by Cameron Jerome.
Both sides could have earlier had penalties as the ball struck the hands of rival centre-halves Roger Johnson and Robert Huth.
There were no goals at Ewood Park, though Blackburn should have taken the lead against Newcastle as Roque Santa Cruz headed against the post from close range, while Peter Lovenkrands’ chip at the other end came back off the crossbar and Fabricio Coloccini’s superb volley from a well-worked Newcastle corner was pushed over by Paul Robinson.