Barcelona coach Hansi Flick has warned his players against showing "weakness" by arguing with referees after Real Madrid's Jude Bellingham was sent off for talking back to a match official on Saturday.
Referee José Luis Munuera Montero dismissed Bellingham in Madrid's 1-1 draw with Osasuna for saying "f--- you." The England international insists there was a miscommunication and he had actually said "f--- off" in frustration.
Flick has said either comment is disrespectful and that he has told Barça's players to not even waste energy contesting decisions with match officials.
"When you say this to me, I think it's not nice," he said in a news conference when asked for his thoughts on the difference between "f--- you" and "f--- off."
"It's disrespect. For me, it's like that. But I don't have to decide [the punishments]. It's not my thing to decide about this situation.
"I think, and this is always what I say to my players, why you waste time or energy to speak or discuss with the referee about these decisions?
"We have one person on the pitch who is allowed to discuss with the ref and this is the captain. We have to accept that.
"I don't like this behaviour and I said this today to my players because it's very important and it's not good for the team when you do it and get the red card. It's a weakness and we don't like that."
Madrid's dropped points, coupled with second placed Atlético Madrid's draw against Celta Vigo, means Barça could jump from third place to top of LaLiga if they beat Rayo Vallecano on Monday.
Barça are unbeaten in 11 games in all competitions since the turn of the year, but they welcome a Rayo side who have avoided defeat in their last nine LaLiga games, last losing in the league on Dec. 1.
"We don't look to the table," Flick added after watching both of Barça's title rivals slip up this weekend.
"For us, it's very important at the end [of the season] we see what happens. It's a long way to the end. We want to show the performances we did since the New Year started.
"Rayo are doing a really good job. The coach [Iñigo Pérez] is doing unbelievable. They're a brave team and they press and they do it with a real intensity, at home and also away."
Flick has no new injury concerns for the game at the Olympic Stadium, with Ronald Araújo fit despite hurting his ankle last week, leaving Marc-André ter Stegen, Andreas Christensen and Marc Bernal as the only absentees.