The psychological shift was seismic. Real Madrid have endured a season to forget so far, but that is all changing – and where better to change it than in the home of your biggest rivals?
Madrid out-thought, outfought and outclassed Barcelona in their own den in their Copa del Rey second leg. In Madrid, the mood is joyous. Elimination by Barcelona and Manchester United would have marked the end of their season and, almost certainly, Jose Mourinho's job.
Written off after months of infighting between Mourinho and his players, Madrid look more dangerous than at any point this season.
They are injury-free and have a point to prove to their many critics and Cristiano Ronaldo is still smarting after losing out to Lionel Messi for the Ballon d'Or.
On Tuesday in Camp Nou, he was, by a distance, the game's best player and scored for the sixth successive time in the home of Madrid's greatest rivals.
United away is Madrid's next cup tie in the Uefa Champions League and Sir Alex Ferguson, the United manager, was there to see a solid Madrid defence and their frighteningly quick counter-attacking.
Madrid are not going to win the league, but lifting two cups will be viewed as a huge triumph.
Mourinho could have gloated in the news conference after the game, instead he sent a player he had fallen out with to speak to the media. He does things his way and, for the moment, it has started working again.
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