Barcelona coach Xavi Hernández believes that intelligence and nerve control are the most important means of winning the Clásico against Real Madrid.
Speaking at the match's press conference on Friday, the coach said: "We are facing the biggest match in the world, I think the chances of both teams are 50:50, and the atmosphere of the match is expected to be tense and difficult as usual."
"The key to winning is to be smart, to be able to control your emotions, impose your personality and control the rhythm."
Barcelona have faced a number of injuries in recent times amid uncertainty for everyone except Sergi Roberto, and Xavi may have added to the mystery hours before the upcoming Clasico.
When asked about the injured, he clearly replied: "Only a player who is 100 per cent ready will participate in the game."
"Lewandowski, De Jong, Pedri and Rafinha are in good condition and participated in training, but the medical staff does not want to risk any player."
Xavi was forced last season to change Ronald Araújo's position to become a right-back in order to stop the danger of Vinicius Jr., and whether he will repeat it this season, he replied: "We have Cancelo and this is his main position, but we have a number of options, we will decide tomorrow which one we will adopt.
It is noteworthy that Xavi as a coach of Barcelona played the Clasico 7 previous times between the league, the Cup and the Super, succeeded in winning 4 times and lost 3 others and never drawn.