Real Madrid manager Zinedine Zidane believes his side's derby against Atletico on Saturday is too close to call as both sides are so strong.
Los Blancos currently lead La Liga and are six points above 4th-placed Atleti, who have lost two of their last three league matches.
"It's 50/50 and will be difficult from start to finish. It will be very, very difficult game, but we're used to these matches,” explained Zidane.
“Atletico are a team who improve each year, they are always improving. They have a very good coach, who is doing great work.
"People always say Atletico defend well, but they are much more than that. You see that in all they do."
The 44-year-old also said he was happy to see his compatriot Antoine Griezmann fit for Los Rojiblancos, before giving some fitness updates on his own side.
"For me it's good Griezmann can play tomorrow. I never want player on rival team to be injured. I'm happy for him to have recovered," he continued.
“Karim (Benzema) is in the squad, he is with us, he is better, and I’m happy to have him. He could start tomorrow. We will have to see.
"Casemiro is not yet ready to be with us, he is improving every day, we will see next week if he can train with us.
“Sergio (Ramos) has trained well all week, and we will see tomorrow how we will play.”
