The Spaniard sidefooted Florent Malouda's low shot past Villa goalkeeper Shay Given after being introduced just before the hour mark to add to Josh McEachran's early opener.
Boss Andre Villas-Boas once again shuffled his line-up with Nicolas Anelka starting up front, meaning Didier Drogba and Torres had to settle for a place on the bench. With the game barely under way, Chelsea took the lead. Given did brilliantly to deny Anelka and Malouda but McEachran was on hand to pounce from close range.
A slick Chelsea move 10 minutes before the interval then ended with McEachran sliding the ball through to Anelka but his low shot was held by Given.
Stiliyan Petrov's volley skidded wide six minutes into the second period after the ball fell to the skipper following a corner before Fabian Delph hacked John Terry's towering header from a corner off the line. Villas-Boas then introduced Torres and Drogba with almost an hour gone and the Spaniard netted Chelsea's second within seconds of coming on when he diverted Malouda's low strike past the diving Given. Darren Bent wasted a good opportunity with 11 minutes left when he latched onto a flick-on and raced clear but fired over the crossbar and Emile Heskey shot narrowly wide.