An Oscar free kick and a Federico Fernandez own goal have given Chelsea a 2-1 lead over Swansea City at half time.
Bafetimbi Gomis had two early chances to give the visitors the lead. Firstly, the French striker headed wide from a Jonjo Shelvey corner, before he latched onto a Shelvey through-ball on 15 minutes, only to see his shot cleared off the line by Cesar Azpilicueta.
Chelsea scored the opener five minutes later, as Oscar's free kick to the left of the penalty area missed everyone in the box and reached the far corner of the net.
Willian had a chance to double the hosts' lead soon after, as the Brazilian made himself space in the box, but his shot was drilled wide of the goal.
Swansea found an equaliser on 29 minutes through Andre Ayew, who finished from close range at the second attempt, following a Gomis header that had been kept out by Thibaut Courtois.
But the Premier League champions regained their lead immediately, as Willian's cross deflected off Swansea defender Fernandez for an own goal.
Diego Costa forced a save out of Lukasz Fabianski at the near post, before Gylfi Sigurdsson tested Courtois at the other end.
Stephen Topping
