'I take responsibility' - Barcelona star left devastated after role he played in shock Champions League loss to Atletico Madrid

The complexion of the all-Spanish tie shifted dramatically in the 43rd minute at the Camp Nou. Following a slick Atletico counter-attack, Cubarsi brought down Giuliano Simeone near the edge of the penalty area, sparking a sequence of events that defined the evening. Referee Istvan Kovacs initially brandished a yellow card but was prompted to consult the pitchside monitor by the VAR. After a lengthy review, the official deemed Cubarsi to be the last man and upgraded the punishment to a straight red card, leaving Hansi Flick’s side a man down just before the interval.

Taking to social media after the final whistle, the Masia graduate refused to hide from his role in the defeat. The centre-back acknowledged the gravity of the incident while calling for squad unity ahead of the return leg in Madrid.

"One action determines the match and the tie," Cubarsi wrote on Instagram. "That's football and I take responsibility for the result. There's still a long way to go in this two-match tie, and we're more united than ever: we're a family and we've always shown it. Moving forward, with effort and determination, we'll never give up."

The consequences of the foul were immediate and severe. From the resulting free-kick, Alvarez produced a moment of individual brilliance, curling a precise effort into the top corner to give the visitors the lead. The situation worsened for the hosts in the second period as Sorloth doubled the advantage for Diego Simeone’s side. The Norwegian's strike ensured Atletico take a commanding 2-0 lead back to the Metropolitano.

Flick must now navigate the second leg without one of his most trusted young defenders. While Barcelona created several openings through Lamine Yamal and Marcus Rashford before the dismissal, their lack of clinical finishing has left them on the brink of European elimination.

Barca will now turn their attention to the Catalan derby against Espanyol in La Liga, with them still comfortably at the top of the table, seven points ahead of Real Madrid. After that, Flick's men will look to mount a comeback against Atleti in the second leg next week.