Manchester City salvaged a point with two late goals to draw 3-3 with Sunderland on Saturday but the result helped tip the balance in the Premier League title race more in Manchester United's favour.
Sunderland ended City's perfect home record with two goals from Sebastian Larsson and one from Niklas Bendtner halting their run of 15 straight home league wins this season.
The visitors led 3-1 with five minutes to play before Mario Balotelli, who also scored a first-half penalty, pulled one back after 85 minutes and Aleksandar Kolarov saved a point a minute later.
United, who play Blackburn Rovers at Old Trafford on Monday, lead the standing with 73 points, City are second on 71.
Lowly Queens Park Rangers ended Arsenal's seven-match winning league run with a 2-1 victory at Loftus Road where Adel Taarabt put QPR ahead before Theo Walcott equalised for the visitors.
Samba Diakite scored QPR's second-half winner, leaving Arsenal third in the table on 58 points.
Chelsea let a 2-0 lead slip at Aston Villa who fought back to 2-2 with only 13 minutes to play before Chelsea won 4-2 to move within two points of fourth-placed Tottenham Hotspur who play Swansea City on Sunday.
James Collins and Eric Lichaj hit back for Villa after Dean Sturridge and Branislav Ivanovic scored for Chelsea who recovered to win with late goals from Ivanovic and Fernando Torres.
Wolves are six points adrift at the bottom on 22 points after losing 3-2 at home to Bolton Wanderers who moved on to 28 points. They have the same as QPR and Wigan Athletic, who beat Stoke City 2-0.
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