The hosts took an early lead through David Villa but Joe Cole scored once and set up Didier Drogba for another as the London side earned a precious win.

Chelsea top Group B with four points, one ahead of Valencia and Schalke, who eased 2-0 past rooted Rosenborg.

Valencia started the game in an explosive style, fueled by cheers from their packed stadium and motivated with Chelsea's poor form.

Villa snatched the lead in the ninth minute, fighting for the ball with Chelsea's defenders and eventually going one-on-one with Petr Cech.

The Spanish international buried an ice-cool finish in between the keeper's legs for the opener.

Chelsea leveled 12 minutes later thanks to a brilliant blitz involving Drogba, Florent Malouda and Cole.

Malouda had a quick give-and-go with Drogba on the edge of the area before storming into the box.

The Frenchman crossed on the floor for the anticipating Cole, who easily tapped in.

In the 71st minute, Cole threaded a long ball for a darting Drogba as the Ivorian international outpaced his marker and dinked the ball into the far corner.

In Norway, Schalke had no problems beating Rosenborg to make up for their defeat at home last match.

Jermaine Jones broke the deadlock in the 62nd minute with a close range shot and German international Kevin Kuranyi curled home one minute from time.