The Italian international received his marching orders when he was adjudged to have elbowed Cristiano Ronaldo three minutes after the break with Los Blancos leading 2-1.
The Frenchman believes that his team could have taken a point at the Bernabeu had they not been a man down.
"It was clearly not a red card offence," he told Sky Sport Italia.
"The referee made this decision, so we can't do anything about it now.
"We had a good first half and I think we could've earned a draw here, but when going down to 10 it was more difficult."
The Bianconeri are third in Group B, eight points behind Real and two behind second-placed Galatasaray.