Crespo scored as Chelsea got another victory
Forward Hernan Crespo scored after just seconds of coming on as a substitute and Didier Drogba lashed in the goal of the game as Chelsea romped home in the London derby.
Midfielder Frank Lampard volleyed home against his former club in the 25th minute, though the leaders were pegged back just after the re-start by Marlon Harewood's equalizer.
Crespo, put through by Arjen Robben, rounded Roy Carroll to restore the lead in the 61st minute and Drogba made the third from a tight angle with 10 minutes to go.
A fourth win from their four festive season matches helped Chelsea's canter towards a second consecutive league title.
"That's what we are up to" Lampard told us. "We don't want to let up, we want to keep winning games, keep the gap at the top and if anything make it bigger."