Athletic Bilbao forward Inaki Williams said he was subjected to racist chanting during his side's 1-1 draw away to Espanyol on Saturday in La Liga.
"I'm sad because of the draw but above all because I suffered racist insults, no black player or any player ever wants to hear that," Williams told the club's official media after the game.
"It's completely out of order, people should go to matches to enjoy themselves, to support their team; football is a team sport and should be played in a friendly atmosphere.
"It's a sad day because of these incidents which have no place in football."
Espanyol did not immediately respond to a request for comment.
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