"[The rules] aren't clear for us," Casemiro said after the draw against Atletico Madrid, as quoted by Diario AS.
"If the ball didn't touch [Felipe] on the arm I would have scored and I tried to explain that to the referee.
"It's his decision and we have to respect it. He's a good ref, he went to VAR to look and that's positive, but I tried to explain that if it wasn't touched then I was there behind."
Real Madrid's penalty claims were waived off by the referee after a VAR review.
The handball was not intentional but Felipe's arm was stretched out and the ball changed the direction after it touched the defender's arm.
The Whites scored a late equaliser but are left to rue the referee's decision as the game could have gone differently had he awarded the penalty.
