Real Sociedad suffered a testing encounter away to Barcelona, with Aritz Elustondo's 17th-minute red card contributing to a chastening afternoon in La Liga.
The 10 men did not muster a single shot as two goals in each half secured a 4-0 victory for the title-chasing Catalans.
Any hopes the Basque side had of repeating their victory over Barca in November were diminished by Elustondo’s dismissal for hauling Dani Olmo down. Of course, the defender’s suspension will not apply to the Europa League.
Gerard Martin opened the scoring and Marc Casado deflected in an Olmo strike to swiftly double the advantage.