Barcelona suffered a hangover from their remarkable Champions League comeback against Paris Saint-Germain as Alex Bergantinos's winner 16 minutes from time handed Deportivo la Coruna a famous 2-1 win on Sunday.
Joselu had fired Deportivo into a first-half lead before Luis Suarez levelled in the first minute of the second period.
However, Bergantinos rose highest from a corner to seal Deportivo's first victory over Barcelona since 2008.
Barca's defeat means Real Madrid can go top of La Liga with victory over Real Betis later on Sunday.