The match official has revealed that the left-back insulted him during Sunday's encounter, leaving him no other choice but to send the the Portuguese to the stands
The Portugal international did not feature during Madrid's surprise loss, but was dismissed in the closing stages of the encounter after insulting the match official.
"In the 88th minute, the player (5) Fabio Alexandre Da Silva Coentrao was sent off for the following reason: he contacted me when the game was halted, and insulted me when I stood next to him by calling me a 'son of a whore'," Perez Lasa wrote in his official report, according to Marca.
Coentrao's dismissal will not have any consequences for Wednesday's second leg of the Spanish Supercopa against Barcelona, however, as a suspension will only be valid for La Liga.
Madrid were beaten 3-2 in the first leg at Camp Nou last week. This week's return at the Santiago Bernabeu kicks off at 22:30CET.