If Atletico Madrid fail to stop the Real Madrid juggernaut on Sunday then the race for La Liga will have a clear favourite.
Los Blancos have taken an intimidating total of 41 points from their last 15 league matches, overtaking stuttering Atletico and Barcelona in the process.
Real were five points behind Atletico and Barca at Christmas but are now three points ahead of them. They confirmed their devastating form Wednesday with an impressive 6-1 romp at Schalke in the Champions League.
"It's true that they are playing well at the moment, but no one should doubt that we will be trying to win," said Atletico president Enrique Cerezo Wednesday.
"I don't know whether we will see good football but it will be a hard match, that I am sure of." Atletico - who won 1-0 at Real's Estadio Bernabeu in September - will be without injury victims Tiago and Javier Manquillo. Neither team has suspensions now that Cristiano Ronaldo has served his controversial three-match ban.
Ronaldo is just one goal ahead of Atletico's Diego Costa in the scorers' chart.
Barcelona will be hoping for an Atletico win in El Derby then to go back on top themselves - albeit on goal difference - by beating lowly Almeria at home.
It should have been a peaceful week for Barca, without a midweek match for the first time in four months.
However, it turned out to be a week of tension and rumours, not only because of the Neymar scandal but also because of last Saturday's 3-1 meltdown at Real Sociedad.
For the first time all season, the Catalan media have been whispering that coach Gerardo Martino might not continue beyond June, amid speculation and online polls about a possible successor.
Veteran playmaker Xavi came to Martino's defence Wednesday, saying: "The coach is being blamed at the moment but that is not fair. We are all to blame, we are a team...I see him (Martino) sure of himself and well motivated.
"Now we have no margin for error left, we cannot fail again. But I actually think we are well placed to win trophies at the end of the season." Xavi added that Neymar was not affected by the court case about his transfer. "I see him well, smiling, happy, training well, like all the team." Sunday's other games are Villarreal v Real Betis, Sevilla v Real Sociedad and Rayo Vallecano v Valencia.
