With United facing Liverpool tomorrow the Gunners had the opportunity to pull to within a point, but Sunderland, who had lost four in a row before today, claimed a goalless draw at the Emirates.
Marouane Chamakh headed Jack Wilshere’s cross against the bar after 75 minutes, while at the other end Wojciech Szczesny exorcised some Carling Cup final demons with a great save from Danny Welbeck.
At the other end of the table, West Ham lifted themselves out of the bottom three with a 3-0 win over Stoke at Upton Park.
The Hammers took the lead in the 21st minute as a mix-up between Marc Wilson and Asmir Begovic allowed Demba Ba to tap in, before an unmarked Manuel da Costa rose to head home Thomas Hitzlsperger’s free-kick eight minutes later.
Hitzlsperger’s rocket seven minutes from time made the points safe.
That scoreline was enough to take them above Birmingham, who lost 3-1 to West Brom at St Andrew’s today to give Roy Hodgson his first win as West Brom boss.
Second-half goals from Youssouf Mulumbu, James Morrison and Paul Scharner enabled the Baggies to leapfrog their local rivals in the battle for survival.
Jean Beausejour pulled one back for Blues moments after Mulumbu gave the Baggies the lead, but they were well beaten.
Aston Villa’s woes continued as they lost 3-2 at Bolton in a game they could easily have won.
Villa took the lead as Kyle Walker on the right found Darren Bent to tap home from close range after 15 minutes.
Bent also hit the post for Villa, before Gary Cahill levelled for the hosts on the stroke of half-time.
Villa retook the lead as Marc Albrighton volleyed home Stuart Downing’s cross after 64 minutes, then Ashley Young had a 70th-minute penalty saved by Jussi Jaaskelainen after being fouled by David Wheater.
Cahill blasted Bolton level after 75 minutes and Ivan Klasnic won it for the hosts four minutes from time.
Bobby Zamora scored his first home Premier League goal in more than a year to give Fulham a 3-2 win over Blackburn at Craven Cottage.
Fulham went ahead eight minutes before the break as Damien Duff fired from a narrow angle and Blackburn goalkeeper Paul Robinson could not save after a slight deflection, but Grant Hanley’s deflected shot in stoppage time levelled things up.
Duff beat Robinson at his near post to put Fulham back in front a minute before the hour mark, but Junior Hoilett volleyed Rovers level from close range after 65 minutes.
Zamora, on as a second-half substitute, converted from the spot a minute from time after Hanley fouled Aaron Hughes.
There was something to smile about for Everton fans as they came from behind to win 2-1 at Newcastle.
Kevin Nolan’s 23rd-minute shot should have been held by Tim Howard, who instead pushed the ball straight to Leon Best to put Newcastle ahead.
But Everton levelled through Leon Osman, who side-footed the ball past Steve Harper after good work by Mikel Arteta, and Phil Jagielka completed the turnaround nine minutes before the interval.
Best had a goal ruled out after 78 minutes for a foul as the Toffees held on.