Real Madrid travel to Catalonia six points behind their fierce rivals after nine La Liga matches. Mourinho's side beat RB Leipzig in the Champions League in midweek, while Barcelona suffered a 4-2 defeat against Paris Saint-Germain.

However, the Portuguese coach does not believe Barcelona's European setback will affect their confidence ahead of one of football's biggest fixtures.

"We're in a good run of form, we're playing well, we're scoring goals, but the Clasico doesn't matter what you've done before. It has no influence. It's truly different," Mourinho said.

The Real Madrid boss also dismissed suggestions that Sunday's match would determine whether his team could win trophies this season, delivering a confident message about his ambitions.

"No, Real Madrid with Mourinho wins titles," he declared.

Mourinho was equally clear when asked about Yamal, who could pose a major threat to Madrid's defence. While acknowledging the teenager's quality, he insisted his team would not reshape its entire approach to deal with one opponent.

"He is a great player, and great players deserve respect," Mourinho said.

"But respecting someone is one thing, while changing your plans and structures and forgetting your own identity is another. We will not do that, either against him or against another player with his exceptional quality."

The coach also defended Real Madrid against comparisons with Barcelona, arguing that his team remains at an early stage of its development.

Mourinho pointed out that he had been working with his players for only three months, with a disrupted pre-season and international breaks limiting the time available to build the team.

"We are a long way from being a finished product," he explained.

"This is the beginning. We are at a stage where the coach is getting to know the players, analysing them and defining paths, while they are getting to know the coach."

He added that comparing Madrid with a team that had been working together for several years was unfair, although he acknowledged that Barcelona sometimes deserved the praise they received.

Mourinho also refused to reveal his tactical approach for Sunday's encounter, particularly when questioned about whether Madrid would attack more aggressively to exploit Barcelona's defensive weaknesses.

"You're smart, but I'm not stupid!" he joked when pressed for details.

The former Chelsea, Manchester United and Real Madrid coach also praised Barcelona manager Hansi Flick, describing him as a great coach who was doing an excellent job.

Meanwhile, Mourinho renewed his concerns about the disclosure of refereeing appointments before matches, arguing that the issue was not the identity of the officials but whether the rules were being followed.

"The referee's name never bothers me. I start from the principle that the referee is good," he said.

"What bothers me is when the rules are broken and, according to internal information, the situation is still not clear."

Jose Mourinho backs Real Madrid plan to contain Lamine Yamal in El Clasico