Two fine goals from Lionel Messi helped Barcelona to a comfortable 3-0 win over last season’s Champions League finalists Juventus at the Nou Camp.
AS Roma clung on a for a 0-0 draw at home to Atletico Madrid in their opening Champions League group-stage game thanks to a string of fine saves from goalkeeper Alisson on Tuesday.
Bayern Munich beat 10-man Anderlecht in their Champions League opener, although the German champions were unconvincing.
Manchester United made a winning return to the Champions League with a deserved home victory over Swiss side Basel.
RESULTS
Chelsea 6-0 Qarabag FK
Roma 0-0 Atletico Madrid
Olympiacos 2-3 Sporting Lisbon
Manchester United 3-0 Basel
Benfica 1-2 CSKA Moscow
Barcelona 3-0 Juventus
Bayern Munich 3-0 Anderlecht
Celtic 0-5 PSG