The Dutchman couldn't understand why he was dismissed in the second half of the 2-1 defeat at Camp Nou
Ronald Koeman insisted that he was "disrespected" by the fourth official during Barcelona's loss to Granada and was left bemused after being shown a red card.
Barca missed the chance to go top of La Liga after being beaten 2-1 by Granada at Camp Nou on Thursday night.
Lionel Messi opened the scoring only for Darwin Machis and Jorge Molina to complete a second-half turnaround for the visitors, with Koeman forced to watch the last portion of the game from the stands after being dismissed by match referee Pablo Gonzalez.