Sergio Ramos does not feel he "crossed any lines" with his criticism of referee Alejandro Hernandez Hernandez following Real Madrid's shock loss to Levante.
Madrid captain Ramos was booked after just 10 minutes of the 1-0 defeat on Saturday and the centre-back also felt Los Blancos were twice denied penalties.
The Spain centre-back let his frustration be known after the game when he said: "I'm annoyed with Hernandez Hernandez.
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"Referees were more respectful before and captains could speak to them. The arrogance is something that you have or you don't have.
"I asked if he had any personal problem with me and, if he did, to tell me so we could work it out. We're annoyed."
It is not the first time Ramos has taken issue with the official this season, having been left annoyed when VAR was not used to check a couple of calls in December's goalless Clasico with Barcelona.
But Ramos justified his comments after the Levante defeat when previewing Madrid's Champions League last-16 first-leg tie against Manchester City .
"I don't feel persecuted in Spain, but the philosophy is different in Europe, a bit more permissive in some things," he said.
"The last game [Levante] was something personal, but generally I feel I have a good relationship with refs.
"I've never said anything out of place, nor never lacked respect for any referee. This is a democracy, and you can speak your mind, I don't think I've crossed any lines."
The Blancos will need Ramos to be fully focused on events in the present when they play host to City on Wednesday.
Pep Guardiola’s side are set to arrive in the Spanish capital aware that 2020 could represent their last opportunity to conquer the continent for some time.
They have been stung by a two-year ban from Champions League competition for breaching Financial Fair Play regulations.
Those sanctions are likely to fuel the Blues’ desire to get over the line this season and end their long wait for European glory.
Madrid, though, are 13-time winners and will believe that they are more than capable of claiming a Premier League scalp and booking their place in the quarter-finals.