Barca were thrashed 4-0 at Atletico Madrid in the first-leg of their Copa del Rey semifinal last night.
The Blaugrana was left furious about the refereeing of Martínez Munuera, whose performance was decisive in disallowing a Barcelona goal after a seven-minute VAR review and sending off Eric García in the final ten minutes, says Marca.
The anger is so great that Barcelona is considering filing a formal complaint with the Federation regarding Munuera's refereeing.
First and foremost, the complaints will focus on the disallowed goal, which was reviewed at length in the VAR room.
Barcelona believes the offside call should have been semi-automatic and not debated for so many minutes. The club will demand an explanation for this decision.
The complaints will also focus on defender García's sending-off, which they consider unfair. And, above all, on the perceived double standard.
There was an earlier incident involving Atlético Madrid where a player, specifically Giuliano Simeone, wasn't sent off for a tackle on Alejandro Balde.
The return to Barcelona was bitter, "We're always wronged by the refereeing" and "I've never seen anything like this with VAR" were some of the phrases overheard as the players boarded the team bus at the Metropolitano.