An error from Petr Cech allowed Wigan to hold Chelsea to a 1-1 draw at the DW Stadium. Hugo Rodallega's limp shot was begging to be collected, but Cech spilled the ball straight into the path of Jordi Gomez, who tapped in from close range.
Chelsea had earlier taken the lead through Daniel Sturridge on 59 minutes after the forward plucked Ashley Cole's cross-field ball out of the air before lashing a right-foot shot across Ali Al Habsi and into the corner of the net.
The Blues' grip on a Champions League spot has loosened: they are third, three points ahead of fifth-placed Arsenal, having played a game more than their London rivals. Wigan are one point from safety in 18th.
Bolton remain rooted to the bottom of the table, five points from safety, after losing 2-0 to Fulham at Craven Cottage. The defeat cranks up the heat on Trotters boss Owen Coyle, whose side have won just three league games all season.
Bolton held their own for most of the first half, but were undone by a deadly one-two punch from Fulham, who scored twice in as many minutes.
First, Clint Dempsey converted Bryan Ruiz's cross, then Ruiz went clean through on goal and produced an inventive chip over Jussi Jaaskelainen's head. Wanderers responded with an improved performance in the second half, but never seriously threatened to get back in the game as Fulham recovered in style from the midweek Europa League exit.
There was no organised protest from the Blackburn fans against boss Steve Kean before the match with West Brom, but there was anger at the final whistle as Rovers were beaten 2-1.
Following a forgettable opening period in which both teams struggled for fluency, James Morrison sprinkled some stardust on the game by putting the Baggies ahead on 50 minutes with a terrific 25-yard volley. But West Brom have struggled to keep clean sheets all season, and their defensive weakness was highlighted again as Scott Dann, scoring for the first time in a Blackburn shirt, equalised with 20 minutes left. Paul Robinson launched a long ball forward, Chris Samba won the flick and Scott Dann pounced to stab home from six yards.
There was a late sting for Kean, however, as Peter Odemwingie cut in off the right flank and lashed a glorious left-foot curler past Robinson. The Scot celebrated one year in charge at Rovers this week; he looks unlikely to manage another 12 months.
Newcastle have now taken just two points from their last five games after a 0-0 draw with Swansea at St James' Park. They were unlucky not to win, but their dreams of a Champions League place are fading fast: they are four points behind fourth-placed Tottenham, who have played two games less.
The Magpies grew in confidence as the first half wore on, and twice went close, first when Demba Ba volleyed against a post, then when the returning Fabricio Coloccini headed against the frame of the goal. They put Swansea under swathes of pressure in the second period without finding the net, and the Premier League newcomers got a draw that moves them six points clear of the relegation places.
Everton showed why the January arrival of Landon Donovan cannot come soon enough as they were held to a 1-1 draw against Norwich at Goodison Park. David Moyes' men wasted a hatful of chances, highlighting their desperate need for striking reinforcement.
The Toffees were utterly dominant in the first half hour, with Russell Martin forced to clear off the line from Leon Osman - but Norwich took the lead thanks to a majestic strike from Grant Holt, who twisted and turned in the area before curling in his sixth goal in his last eight Premier League games. Holt was lucky to stay on the pitch in the seconds before the break, having put his arm into Marouane Fellaini's face following a tussle.
Everton pushed hard in the second period only to find their efforts repelled by former Goodison goalkeeper John Ruddy, who was in inspired form. The hosts finally found a way through with ten minutes to go, Osman tapping in following fine work from Royston Drenthe. Norwich were pinned on the ropes in the closing stages, but held on to earn a point.
Wolves remain deep in the relegation mire after Stoke managed a 2-1 comeback victory at Molineux. Stephen Hunt put Wolves in front from the penalty spot on 15 minutes following Jonathan Woodgate's clumsy challenge on Matt Jarvis. Woodgate had already been booked, but was surprisingly not shown a second yellow that would have compounded the Potters' misery - and four minutes later, he was hauled off by boss Tony Pulis.
Another of Stoke's defenders equalised just before the hour as Robert Huth thundered in a free-kick that took a heavy deflection off Kevin Doyle. Wolves never recovered from the setback, and Peter Crouch's header on 70 minutes completed the turnaround. Wolves stay 17th, while Stoke go to eighth.
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