Frank Lampard chipped in with his customary goal from the spot early in the second half, before substitute Didier Drogba made the victory safe with a blistering right-foot strike late in the game.
After conceding a late equaliser against Everton in midweek, Rovers boss Mark Hughes made two changes to his back four - new signing Andre Ooijer was handed his debut in place of Andy Todd and Lucas Neill returned from suspension to replace Michael Gray at left-back.
Jose Mourinho made three changes to the side that suffered the shock defeat at Middlesbrough on Wednesday night, with Khalid Boulahrouz and Michael Ballack making their Blues' debuts and Petr Cech returning to the side for his first start of the season in place of Carlo Cudicini in goal.
In a fixture with a lot of recent history, both sides made a tentative opening to the game. From almost identical positions, Michael Essien blazed over on two minutes, before Robbie Savage followed suit with a left-foot strike just five minutes later.
The nerves continued just before the quarter-hour mark, when Ooijer's unsighted back-pass almost let in Salomon Kalou, but Brad Friedel just reacted in time to clear his lines.
The closest either side came to breaking the deadlock in the first half came on 21 minutes and twice involved the Chelsea number 21. After bringing down David Bentley 25 yards out from goal, Morten Gamst Pedersen's free-kick then struck Kalou and deflected just inches over a stranded Cech's bar.
Disappointing in the first half, Chelsea looked an altogether different prospect after the break and took the lead less than five minutes in.
After a debatable foul by Savage, Ooijer was adjudged to have tugged back John Terry while trying to defend Lampard's free-kick and referee Mark Clattenburg pointed to the spot.
Up stepped Lampard and the England man made no mistake, firing a crisp right-foot strike into the bottom left-hand corner, with Friedel diving the right way.
Just six minutes later and Rovers almost had an equaliser that their first-half endeavours deserved. Man-of-the-match Brett Emerton supplied the perfect cross to the back post and, after coolly bringing down the ball on his chest, Benni McCarthy was denied his second goal in as many games by a world-class Cech save.
Drogba replaced the ineffective Kalou shortly after, but it was Rovers who felt hard done by at the other end. On 63 minutes, Jason Roberts appeared to be pulled back by Ricardo Carvalho inside the box but, after staying on his feet, the appeals for a penalty were waved away.
Neill flashed an effort just wide on 78 minutes but, with extra bodies pushed up front, Chelsea struck on the break. Essien played the inch-perfect throughball for Drogba and, after holding off the challenge and despairing lunge from Ooijer, the Ivory Coast striker smashed the ball past Friedel, to leaving Rovers still chasing their first three-point haul of the season.