Luis Enrique says he understands why Barcelona players reacted furiously to their Copa del Rey defeat to Athletic Bilbao, with Gerard Pique reportedly facing a ban over his post-match comments.
Barca left San Mames with a 2-1 defeat in the first-leg fixture, which saw Athletic reduced to nine men in a clash overshadowed by the performance of referee David Fernandez.
Raul Garcia and Ander Iturraspe were shown second-half red cards, but Athletic strike Aritz Aduriz escaped punishment for striking Samuel Umtiti in the throat, while Barca were further enraged when Neymar was denied a certain penalty.
Pique said afterwards: "We know how this works." – hinting at a long-running Catalan conspiracy that Real Madrid are favoured by the Spanish federation.
"When you don't get what you think you deserve in a game it's normal that players can react that way," Luis Enrique told reporters ahead of Sunday's LaLiga trip to fourth-placed Villarreal.
"There was a lot of tension building among the players in the first half so those were the reactions.
"Players need to control their emotions as much as possible."
He added: "I always think we have to be cautious with our attitude to refereeing the professionals and the people in the football family.
"It's difficult to make a decision in a split second and in this country we play the game of analysing what happened in games and focus on these things.
"So I think we need to draw a line under what we say and that's what I try to do is show respect."
Barca travel to El Madrigal six points behind Madrid in the league, after Zinedine Zidane's side demolished Granada 5-0 on Saturday.
Fran Escriba's side have only been beaten once on home turf in the league this season, beating Atletico Madrid 3-0 last month.
But Luis Enrique says his side still have wriggle room in the title race.
"I'm sure we do," he said.
"I bet that there's no team who will win every remaining game but it's true we're not in the position we like to be.
"We can only put pressure on the leaders by winning every game. We're not going to win every game this season, we wish we could but it won't happen, there's a long season still to go."