Two first-half goals gave Chelsea a 2-1 home victory over a Crystal Palace side whose relegation worries increase.
Willian's strike and a Martin Kelly own goal were enough for the champions despite the visitors producing an improved performance after the break that brought a late goal for Patrick van Aanholt.
Chelsea made the early running in a muted Stamford Bridge atmosphere and almost broke the deadlock after only nine minutes when Wayne Hennessey kept out an effort from N'Golo Kante as striker Olivier Giroud tried to make contact just in front of him.
Andros Townsend blasted a powerful effort just over the top soon afterwards, but Chelsea were soon back on the attack and Willian forced Hennessey into a low save when he tried his luck from distance.
And with 25 minutes played the champions broke through, Willian trying another strike as visiting defenders backed off him and the ball taking a slight deflection off Kelly on its way beyond Hennessey.
Giroud headed over from a Davide Zappacosta cross, but the Blues did not have to wait long before doubling their advantage.
This time, the unfortunate Kelly found himself credited with an own goal when Eden Hazard and Zappacosta started a move that ended with the ball coming off Hennessey and then off Kelly before going in.
Hazard was causing all sorts of problems for Palace and thought he had made it 3-0 just before the break only for an offside flag to go up after James Tomkins had somehow cleared a Giroud shot moments earlier.
Palace boss Roy Hodgson made a half-time change as he tried to find a route back into the game, bringing on Wilfried Zaha for Christian Benteke.
And Hodgson's move almost paid rapid dividends as Palace came forward and, amid defensive uncertainty from the home side, Alexander Sorloth hit the post for the Eagles.
At the other end. Tomkins was again to the fore for the visitors as his superb block thwarted Willian, and Hennessey showed sharp reflexes again as he came off his line to deny Hazard.
Patrick van Aanholt had a volley saved and, at the other end, a Willian free kick was repelled by Hennessey.
Kante made a key interception on the edge of the box as Palace striker Sorloth tried to set up Townsend, and then it was Chelsea's turn to hit the post as Giroud's attempt cannoned off the woodwork after Marcos Alonso had crossed.
Giroud then came off, making way for Alvaro Morata, who had an effort deflected wide as he looked for his first league goal since Boxing Day, while Townsend made way for Lee Chung-Yong for Palace.
Sorloth had a late effort ruled out for a foul as Chelsea, who brought on Pedro for Cesc Fabregas and Tiemoue Bakayoko for Eden Hazard as they seemed set to coast to the finishing line.
But Van Aanholt gave them something to worry about when he prodded home an effort with one minute of the 90 remaining.