Former Real Madrid full-back Roberto Carlos stressed the importance of the forthcoming showdown with Atletico Madrid by saying a derby defeat is like losing a World Cup final.
City rivals Atletico and LaLiga-leading Madrid will clash at Vicente Calderon on Saturday.
Madrid top the league standings, six points clear of fourth-placed Atletico, whom they trumped in last season's Champions League final.
Roberto Carlos played in many derby fixtures during his illustrious 11-year period at the Santiago Bernabeu and the 2002 World Cup winner talked up the significance of claiming bragging rights.
"The preparation for a Clasico or a derby is no different from that for any other game but there are other things which need to be done because of what goes through the minds of the players," Roberto Carlos - winner of four LaLiga titles and three Champions League crowns with Madrid - said at an event via AS.
"They will be wondering what will happen in the week following the game, how they will be received by their fans at their stadium.
"Because losing a derby or a Clasico is like losing a World Cup final."