Portugal star and captain Cristiano Ronaldo was left feeling frustrated following his side's 0-0 draw with the Ivory Coast.

The Real Madrid man felt he was not protected by the referees as he was continually grounded by Ivorian defenders and questioned the yellow card he received in the 20th minute after a run in with Guy Demel.

"Sometimes it's difficult that the referee doesn't give fouls because he thinks I dived," he said.

"I know the game is very quick and the players are very quick, but sometimes I don't understand the decisions of referees.

"I respect them, but sometimes I don't agree because they don't protect the dangerous players.

"In the first half, someone tackled me and I was given a yellow card. I didn't do anything, but he gave me a yellow card.

"Sometimes I don't understand, but that's football. I know I don't have to react if I get a yellow card.

"I don't want to speak about the referee. I respect the decision and I want to be focused on helping my team and to do my best."