Didier Drogba's early double stunned the home side, as Alex and Joe Cole concluded the victory for the Premiership side.

Chelsea are clear on top of Group B with 11 points, four ahead of Rosenborg, who were fortunate to see Schalke and Valencia play out a goalless draw at Mestalla.

The Blues needed seven minutes to open the scoring when Drogba followed in Cole's blocked shot to hit the net in rage, before the Ivorian hitman grabbed his second with a close-range finish in the 20th minute.

Five minutes from the break, Brazil center-half Alex smashed a trade-mark freekick to make it three.

Substitute Andrei Shevchenko came close in the 73rd minute, but his effort was denied by Lars Hirschfeld, who failed to stop Cole on the rebound.

Valencia Crash Out

At Mestalla, 10-man Valencia's hopes of reaching the second round faded after they were held to a 0-0 draw with Schalke.

The Primera Liga side was reduced to ten men in the 32nd minute, when skipper David Albelda was sent off for a reckless tackle.

Valencia have four points at the bottom, while Schalke lie third on five points, with one match to go.