Chelsea recorded an impressive 11th successive victory in the Premier League as Diego Costa's brilliant first-half header proved the difference in a well-contested match with Crystal Palace.
In an even opening period, Palace had a great opportunity to open the scoring but Jason Puncheon, who missed the Manchester United defeat through suspension, scuffed his right-footed shot wide of Thibaut Courtois' goal.
And Costa made Puncheon pay for that miss by leaping above Scott Dann to head home Cesar Azpilicueta's superb cross on the stroke of half-time.
Antonio Conte's men continued to knock on the door for a second goal in south London but found Eagles keeper Wayne Hennessey in wonderful form.