Unbeaten Arsenal stretched their lead in the Premier league to five points after a 2-1 win at Aston Villa on Saturday while Chelsea beat West Ham United 1-0 to overhaul Manchester United and go second.
First-half goals from Mathieu Flamini and Emmanuel Adebayor cancelled out Craig Gardner's 14th-minute strike and Arsenal, dominant in the first half, survived concerted pressure from the home side in the second to take all the points.
Chelsea midfielder Joe Cole sank his former club, rounding Robert Green in the 76th minute to chip right-footed into the top of the net in Saturday's early kickoff.
Chelsea, now unbeaten in 70 home league games at Stamford Bridge in a run stretching back to February 2004, have 31 points from 15 matches.
Arsenal, are on 36 with a game in hand while champions Manchester United, on 30 from 14 games, host Fulham at Old Trafford on Monday.
Sven-Goran Eriksson's Manchester City failed to make the most of their city rivals' absence from Saturday's fixtures. They needed a win to go back above Chelsea but were instead held 1-1 at struggling Wigan Athletic.
City remain fourth, level with United on 30 points but behind on goal difference. Fifth-placed Liverpool host Bolton Wanderers on Sunday.
Steve Bruce's return to the JJB Stadium as Wigan manager started in the worst possible fashion, with Brazilian Geovanni putting City ahead in the first minute before Paul Scharner equalised with a diving header in the 25th.
Paul Jewell, who kept Wigan up at the end of last season, started his reign at bottom club Derby County with an agonising 1-0 defeat at Sunderland.
Anthony Stokes scored the 90th minute winner with an overhead kick from the right side of the box that lifted Sunderland out of the bottom three and up to 14th place.
"It's a kick in the teeth for us...," Jewell said. "We know we are up against it but the lads gave me everything they had today... We're disappointed but I wouldn't say we crumbled."
Middlesbrough replaced north-east rivals Sunderland in the relegation zone after a 1-1 draw at Reading.
ARSENAL FORTUNATE
Everton, who thrashed Sunderland 7-1 last week, were unable to repeat their heroics and drew 0-0 at Portsmouth, while Blackburn Rovers hammered suffering Newcastle United 3-1 at Ewood Park.
While Arsenal provided Villa with a masterclass in passing football in the first half, they will have felt fortunate to leave Birmingham with all three points after Martin O'Neill's side dominated the second.
Gardner's neat half-volley had given the home side hope, but Flamini sent a searing low left-foot shot from 20 metres into the net for the equaliser nine minutes later.
"We worked very hard for it," Flamini said. "It was a bit difficult in the second half but we defended well and the important thing is we got the three points."
Adebayor headed Arsenal's second goal in the 36th, putting away a Bacary Sagna cross after a typically tight passing move.
Villa discomfited the leaders throughout the second half and John Carew's header hit the bar in the 62nd minute but their industry was in vain and Arsenal survived.
Chelsea kicked off the day's programme with the London Derby but there was little entertainment during a first half littered with fouls and eight bookings.
"We were a bit nervous because we were tired but at the end we stayed calm and we had this chance to score," Chelsea striker Didier Drogba told Sky Sports television.
"It was a physical game and I think the referee had a great game, it's not easy to ref in a big derby like this one. He did his job and I think the players in the second half were a bit more responsible."
The striker complained to the fourth official early in the first half, with television images suggesting he had been troubled by a fan shining a laser pen in his eyes.
"It was difficult because you see this green light but this was a stupid fan, I think," said the Ivory Coast player.
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