Rapid Vienna scored a goal in either half to condemn Chelsea to a 2-0 defeat in the opening match to be played at the Allianz Stadion.
The Blues, under the management of new boss Antonio Conte for the first time, were behind inside eight minutes following Joelinton's smart finish.
An improved showing almost saw Conte's men level up in the remainder, but Tomi Correa came off the bench to add the game's second goal for Rapid late on after an error from Branislav Ivanovic at the back.
Relive how the 90 minutes of action unfolded with Sports Mole's live text coverage below.
STARTING XI: Begovic; Ivanovic, Djilobodji, Terry, Baba Rahman; Mikel, Matic; Loftus-Cheek, Moses, Willian; Costa
SUBS: Blackman, Delac, Hector, Miazga, Aina, Chalobah, Kenedy, Cuevas, Oscar, Atsu, Traore, Remy
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