Barcelona coach Ronald Koeman has defended centre-back Gerard Pique's right to make comments about referees favouring Real Madrid.
Pique, who is injured, appeared on YouTube show Post United last week and was asked about a comment last year by former referee Eduardo Iturralde that 90% of referees in the country supported Real Madrid.
The defender said if that was the case then it was natural that match officials would give Real decisions, even if it was subconscious - leading the Spanish FA (RFEF) to open a disciplinary investigation into Pique's remarks.
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"It's not my problem. I won't get involved with Pique's comments, he's responsible and experienced enough to say (what he thinks)," Koeman told a news conference ahead of Saturday's La Liga game with Alaves at the Camp Nou.
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"We have to be careful because you can get into trouble over small things. You have to try and be critical but always with respect and words that they can't do anything about."
Barca on Thursday posted a video on their Twitter account of an incident in their 2-0 defeat at Sevilla in the Copa del Rey semi-final, first leg in midweek that they believed should have been given as a penalty.
Koeman distanced himself from the post, although he said the referee got it wrong.
It wasn't my decision to tweet the video. But for me it's a penalty. The referee said it was a foul outside the box; everyone saw that it was inside.
"I don't understand why VAR doesn't step in. It's not that complicated. Mistakes can be made, no problem, we have to look forward."
Pique will miss the Basque side's visit as he continues to recover from a long-term knee injury.
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Koeman will also be without Ronald Araujo, Martin Braithwaite, Philippe Coutinho, Sergi Roberto and Ansu Fati, but welcomes back Sergino Dest and Miralem Pjanic.
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