John Terry's early header and Cesc Fabregas's second-half strike restored Chelsea's three-point Premier League lead heading into a busy Christmas programme after a 2-0 win at Stoke City.
Chelsea were ahead inside two minutes at the Britannia Stadium when Terry met a Fabregas corner with a powerful downward header.
Stoke pushed forward after the break without ever causing fit-again Chelsea keeper Thibaut Courtois many problems and Fabregas sealed victory with a scuffed finish 12 minutes from time.
"These victories mean more than three points, to win and get three points the players need the right spirit and mentality, to win here they must be a really very good team with the capacity to adapt to Stoke's style of play," Chelsea manager Jose Mourinho told the BBC.
Chelsea, who host West Ham United on Friday, have 42 points from 17 games with Manchester City, who visit West Brom the same day, on 39 and Manchester United on 32.