Real Madrid's official channel aired a segment more than 24 hours before the Clasico, comparing red cards and disallowed goals while invoking the Negreira case.
Jorge Valdano said Barcelona are clear favourites for the 25 October Clasico and said the Negreira case should already have been settled.
Barcelona host Real Madrid in the first Clasico of the season at Camp Nou, with disputes over Javier Tebas, referees and the Negreira case adding to the buildup.
Enric Masip, an adviser to Barcelona president Joan Laporta, criticised Real Madrid before Sunday's Clasico over references to the Negreira case.
Real Madrid supporters displayed a banner about the Negreira case during the second half against Leipzig, with chants lasting about five minutes.
Ibrahima Konaté spoke before Real Madrid's meeting with Leipzig, addressing the Ceuta shirt controversy, Mourinho and the team's priorities.
Real Madrid called for Javier Tebas to resign after he compared the club's media tactics to Goebbels-style propaganda techniques in posts on X.
