|Berbatov's treble took United level on points with City and closed the gap in terms of goal difference [AFP]
Dimitar Berbatov scored a hat-trick as Manchester United beat Wigan Athletic 5-0 to go level on points with Manchester City, with the Premier League leaders being held 0-0 at West Bromwich Albion.
Berbatov scored twice before converting a late penalty, with Park Ji-Sung and Wigan old boy Antonio Valencia adding United's other goals against the visitors who had Conor Sammon sent off late in the first half.
Chelsea's faltering title challenge suffered another blow when they were held 1-1 by neighbours Fulham in an early kickoff at Stamford Bridge, the home team registering their third successive league draw.
Juan Mata scored after 47 minutes for Chelsea, lashing in a left-foot shot from the edge of the box, before Clint Dempsey equalised nine minutes later with a close-range effort after good work by Bryan Ruiz.
United's second successive 5-0 victory – they also thrashed Fulham on Wednesday – allowed them to halve their goal difference deficit on City who started the day with a plus-10 tally over their neighbours and ended it on plus-five.
The last four league matches for United have produced 16 goals for and only one against.
"Today's result pleases me considering the injuries we have had. We had 10 players missing and (defender) Jonny Evans was taken off at half time," manager Alex Ferguson told Sky Sports on Monday.
"In a close game I would have worried about that. We ended up with a back four that has never played together."
At the Hawthorns, West Brom became the first team to prevent City scoring in the league this season.
"Today was difficult," said City manager Roberto Mancini.
"When you play a team who have all their players behind the ball at home, if you don't score in the first half it's not easy.
"It is impossible to score three or four goals in every game. There will be some moments in the year when you won't score."
Liverpool remained sixth with 31 points after being held to a surprising 1-1 home draw by bottom club Blackburn Rovers at Anfield.
A Charlie Adam own goal put the visitors ahead at the end of the first half before Maxi Rodriguez equalised eight minutes after the break.
Blackburn manager Steve Kean, who has been under intense pressure from fans to quit all season, enjoyed the moment.
"It was a patched-up team because we have so many players injured and then we lost our goalkeeper (Paul Robinson) but Mark Bunn came in and made some great saves," said Kean.
"We have got a very young team at the moment but we are digging in and ... I thought my lads were exceptional."
Blackburn narrowed the gap on their nearest rivals after 19th-placed Bolton Wanderers lost at home for the eighth time in nine league matches, going down 2-0 to Newcastle United.
It was a welcome win for Newcastle who ended a run of six matches without a victory thanks to second-half goals by Hatem Ben Arfa and Demba Ba.
Sunderland and Everton drew 1-1 at the Stadium of Light, Jack Colback scoring for the home side after 26 minutes and Leighton Baines equalising with a 51st-minute penalty.
Last year's World Cup final referee Howard Webb ruled Leon Osman was fouled although TV replays suggested the Everton midfielder missed his kick completely, took a lump out of the turf and then fell over without being challenged.
Stoke City and Aston Villa drew nil-nil in the late game.
City and United have 45 points from 18 games followed by Tottenham Hotspur on 35. Spurs have two matches in hand and visit Norwich City on Tuesday.
Chelsea are fourth with 34 points from 18 followed by Arsenal (32 from 17) who host Wolverhampton Wanderers on Tuesday.