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Chelsea kick off the defence of their European crown with a mouth-watering clash with Italian giants Juventus at Stamford Bridge.
Danish side Nordsjælland join Malaga and Montpellier in making their debut in the competition, with a tough away trip to Shakhtar Donetsk.
Bayern Munich will be out to prove they have erased the bitter taste of last season's final defeat by Chelsea when they host Spain's Valencia.
BATE Borisov travel to northern France looking to get off to a good start in their bid to get past the group stages for the first time.
Lionel Messi is expected to return for Barca as they kick off their bid to make it four Champions League titles out of the last eight.
Celtic welcome two-times winners Benfica to Parkhead in the knowledge the Portuguese side have lost both their previous Champions League away games against the Hoops.
Manchester United begin a Champions League campaign for the 17th consecutive season - the longest current run - against Turkish side Galatasaray.
Braga make just their second appearance in the competition while Cluj take their bow for a third time.
- Champions League