The left-back entered the match in the 70th minute, replacing Álvaro Carreras, with Real Madrid already leading 2-0. Rather than receiving a routine welcome from the home crowd, Cucurella found himself targeted whenever he touched the ball.
The reaction initially appeared baffling inside the stadium. However, the explanation lay in the presence of travelling RB Leipzig supporters, some of whom were reportedly seated among the home fans.
Security arrangements had anticipated around 2,000 German supporters in a designated section of the stadium. According to reports, additional Leipzig fans obtained tickets through resale and alternative channels, spreading throughout the ground rather than remaining together in one area.
That distribution made the whistles sound as though they were coming from across the Bernabéu, creating confusion over whether Real Madrid supporters themselves were jeering the defender.
The hostility was rooted in one of the most controversial moments of the 2024 European Championship. During Spain's quarter-final against Germany, a Jamal Musiala shot struck Cucurella's arm during extra time, with the German players demanding a penalty.
Referee Anthony Taylor allowed play to continue, and the video assistant referee did not intervene. Spain subsequently won 2-1 after extra time, eliminating the tournament hosts before going on to lift the trophy.
The decision remained contentious in Germany, where supporters believed their team had been denied a decisive opportunity. UEFA's subsequent refereeing assessment indicated that a penalty should have been awarded, reinforcing the sense of injustice among those who had criticised the original decision.
Cucurella had already experienced hostility from German supporters during the European Championship, including when Spain faced France in the semi-finals. His appearance at the Bernabéu demonstrated that the controversy had not disappeared with the passage of time.
The episode also produced an unexpected response from the Madrid crowd. Once the situation became clearer, home supporters began applauding Cucurella whenever he received the ball, attempting to counter the hostile reception.
What began as a confusing interruption to a Champions League match therefore became a reminder of how an unresolved refereeing controversy can continue to shape supporters' reactions long after the final whistle.
Real Madrid ultimately completed a 4-1 victory over Leipzig, but Cucurella's reception provided one of the night's most unusual talking points.