Chelsea came from a goal down to claim a 2-1 victory away to Valencia on Wednesday in a game that marked Avram Grant's first game as coach in the Champions League.
The Londoners looked to be in trouble in the Group B match when a dominant Valencia took an early lead after striker David Villa cashed in on some shaky defending to steer the ball past keeper Petr Cech.
But winger Joe Cole put Chelsea back in the match when he put the finishing touch to a sharply worked counter-attack and striker Didier Drogba completed a classic smash-and-grab raid with a sharp finish nine minutes from time.
The win put Chelsea top of the group with four points from two games, one clear of Valencia and Schalke 04 and three ahead of Rosenborg, who lost 2-0 at home to Schalke.
Valencia made the early running at the Mestalla with David Silva lashing over the bar with less than a minute on the clock.
Chelsea failed to take heed, however, and helped by a catalogue of errors in midfield and defence, David Villa put Valencia in front in the ninth minute.
The Spain striker pounced on a poor clearance on the halfway line, collected the ball after it ricocheted off Michael Essien and then steered a shot low to the left of keeper Petr Cech.
Joaquin should have made it 2-0 when he broke down the right just over 10 minutes later but he drilled his shot straight at Cech and Chelsea made Valencia pay when they equalised on the break.
Florent Malouda fired the ball low across the area after a neat one-two with Drogba and Cole got enough of a touch to turn it into the net with Italian leftback Emiliano Moretti trying to block his path.
The goal helped steady Chelsea, who have had a stuttering start to the season and were stunned by the departure of coach Jose Mourinho two weeks ago.
Valencia almost regained the lead when Moretti headed wide of the far post after a corner early in the second half but they were made to pay for their profligate finishing when Drogba hit them on the break once more.
Cole spun round to lose his marker in midfield, steered a pinpoint pass into the path of the advancing Drogba with the outside of his foot and the Ivory Coast striker kept his head to finish off with a fine low shot.
"Everybody has done a good job in the last weeks at a very diffcult time but as I said to them, the players and the staff, a difficult time is a challenge," Grant said. "I am very happy with the attitude."