Jose Callejon has revealed that Real Madrid players are often the victims of racial abuse, and fears that it will be difficult to completely kick racism out of the game.
Barcelona defender Dani Alves complained about racist insults after Wednesday's Copa del Rey semi-final at the Santiago Bernabeu, and Callejon has revealed that the Brazil international is not the only player in La Liga who has to deal with the matter.
"Real Madrid is one of the clubs that has been on the receiving end of the most racist insults. It has happened to us and it is a problem that cannot be completely stamped out," the versatile attacker said at a press conference.
"It happened to [Kevin-Prince] Boateng in Italy and it is a matter of serious concern which we all hope will die out one day once and for all."
Fifa president Sepp Blatter recently stressed that national football associations should punish racism harshly, saying that deducting points and relegating a team would be a good sanction.