Real Madrid have been been reported to the Spanish Football Federation after dome of their suppoirters were accused of racist chanting during the match at Levante last weekend.
Colombian forward Edwin Congo and Ivory Coast midfielder Felix Ettien were the two players targeted by the supporters.
“A group of Real Madrid fans shouted monkey noises whenever Levante’s two black players touched the ball,” said referee David Fernandez Borbalan.
Former Real Madrid player Congo said: “It’s upsetting when this happens.”
Racist behaviour by fans has been on the rise in Spanish football this season and Espanyol’s Cameroon goalkeeper Carlos Kameni had a banana thrown at him by an Atletico Madrid fan during his side’s league match on Saturday.
Atletico have been fined twice this season by the Spanish federation and are one of five First Division teams to be punished this season.
Real Madrid were fined from Uefa for similar conduct of their supporters at European games.