Kai Havertz and Christian Pulisic score as the Blues secured a crucial first-leg advantage win over French side Lille.
Havertz, who had already had two attempts on goal in the early minutes, headed down a Hakim Ziyech corner in the eighth minute to give his side the lead.
Pulisic hit the target in the 63rd minute with a curling finish after N’Golo Kante’s surging run and pinpoint pass to double his side lead and secure a crucial first-leg win for the World Champions.
Efforts from all three and from Canadian striker Jonathan David were either blocked, usually by the Bluesbdefensive rock, or collected easily by Edouard Mendy.
Chelsea will face Liverpool in the League Cup final on Sunday, may be satisfied with taking a two-goal lead to Lille for the second leg on March 16.