Nicolas Anelka celebrates after scoring Chelsea's third goal
Nicolas Anelka scored twice as Chelsea claimed a convincing win at rock bottom West Brom to move back above Liverpool at the top of the Premier League table.
The Baggies matched the visitors until Jose Bosingwa caught out Scott Carson, smashing his shot into the top corner.
Anelka ran clear to dink home a second then made it 3-0 before the break after latching on to Salomon Kalou's pass.
Filipe Teixeira fired over for West Brom but Chelsea were always in control despite easing up in the second half.
The win sees Chelsea regain top spot on goal difference, following Liverpool's 2-0 win at Bolton earlier on Saturday.
The Blues' build-up to this game was overshadowed by the furore surrounding Didier Drogba, who threw a coin into the crowd in their midweek Carling Cup defeat against Burnley and is facing Football Association charges over the incident.
He was relegated to the bench here by Luiz Felipe Scolari, who has a crippling injury list to deal with and was down to his last 18 fit senior players at the Hawthorns.
But Scolari's side put those problems behind them with a composed performance that saw them soak up some early pressure before scoring three quick-fire goals to kill the game off before the break.
This was Chelsea's 10th successive away victory - a new Premier League record - and also their seventh on the road in the league this season.
Yet, despite eventually being outclassed, West Brom can still feel hard done by after a bright start which saw them go close in the first minute when James Morrison broke forward and fired inches over from the edge of the box.
The home side had another sight of goal when Borja Balero fed Ishmael Miller inside the area, only for the big striker to scuff his shot harmlessly wide.
A tough night - Mowbray
The Baggies have rightly won plenty of plaudits for their passing football this season but goals - and points - have not been forthcoming and it was a familiar tale of woe for Tony Mowbray's men here.
Chelsea's fluid passing game took time to get going but they were soon creating chances themselves and Scott Carson had to make smart stops from Frank Lampard and Florent Malouda.
The Baggies were still acquitting themselves well, however, but that changed when Bosingwa opened the floodgates with a shot out of nothing on 34 minutes.
There seemed little danger as the Portuguese defender cut in from the right but he surprised everyone - including Carson - with a precise shot into the top corner that the keeper got a hand to but could not keep out.
Anelka's form is fantastic - Scolari
Matters got worse for West Brom four minutes later when Anelka opened his account, latching on to Malouda's header to race away from the home defence and dink the ball over Carson.
And the Frenchman made sure of Chelsea's victory in first-half injury-time when he met Kalou's pass and found a gap between Carson and his near post with a clinical finish.
It was Anelka's eighth goal in his last four league games and how Mowbray must wish he had a striker of his calibre in his squad - Anelka was the biggest difference between the two sides.
Chelsea looked in the mood to add to their tally at the start of the second half when Carson had come off his line to deny Malouda.
But the Blues knew their job was done and they took their foot off the pedal as the game wore on.
Deco fired over and Anelka had a goalbound shot blocked but West Brom had as many opportunities in front of goal in the final half hour.
The Baggies could still not find the target, however, with Teixiera firing over after running at goal and fellow substitute Do-Heon Kim volleying Paul Robinson's cross a yard wide.
West Brom boss Tony Mowbray:
"You always know when you're playing one of these sides, it's going to be a long day if they get their noses in front.
"For 30 or so minutes we didn't hold our own but we were hanging in there, then Boswinga stuck one in and it became a tough one.
"Against these teams you're putting you finger in the dyke at times."
Chelsea boss Luis Feilpe Scolari on Nicolas Anelka:
"He's played almost every game, he has more confidence, he not only plays inside the area but also outside, he is fast, and now that he has confidence he will score more goals for us."
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