India, April 9 -- FC Barcelona and red cards in UEFA Champions League knockouts are turning into a recurring nightmare, one that has hurt them repeatedly in recent seasons, and it struck again against Atletico Madrid. This time, 19-year-old Pau Cubarsi found himself at the centre of the storm with a costly lapse that swung momentum firmly in the opposition's favour.

With around five minutes left before half-time, Cubarsi brought down Giuliano Simeone. While there was little to suggest intent, his positioning left the referee with a straightforward decision, and the red card followed. From that moment, the game tilted. Atletico were handed a free-kick just outside the box, and Julian Alvarez stepped up to deliver, curling in a stunning to...