Arthur played in the first leg of the cup tie against Real on Wednesday, which ended 1-1. His performance came 48 hours after he was spotted attending Neymar's lavish birthday party in Paris.
Barcelona officials are set to hand Arthur a stern warning his for decision to attend the party so close to an important game.
The fact Neymar is a former Barcelona player who controversially quit the club for PSG in 2017 no-doubt hasn't helped Arthur's cause.
And to make things worse for the midfielder, he is now set to miss the second leg against Real through injury.
