Santos midfielder Arouca, who played for Brazil's national team last year, was on the field talking to reporters after a 5-2 win in the Sao Paulo state championship on Thursday when some fans in the stands reportedly called him "monkey."
The midfielder released a statement Friday saying he heard one fan telling him to go look for an African team.
"It's unacceptable that things like this are still happening these days. It shows that the human being still has a lot to evolve and grow," Arouca said. "The greatest pages in the history of our national team were written by players such as Leonidas, Romario and the king, Pele, who are also black. Impunity for these people is just as grave as the acts themselves, so promises alone won't solve this lack of education and humanity."
The Sao Paulo state federation said the stadium in the interior city of Mogi Mirim was being closed until the case was fully investigated. The state's sports tribunal was going to look into it.
The insults came a day after a referee said he was targeted by racist fans before and after a match, and less than a month after another Brazilian player was insulted in a Copa Libertadores game in Peru.
"It's better to block that out, better not to listen to these people, if you can actually call them people," said the 27-year-old Arouca, who scored one of Santos' goals. "It's hard to talk about what is happening these days. It's tough, but we know it happens, not only in football. I just hope someone can do something serious about it because it's lamentable."
While still talking to reporters, Arouca kept looking at the stands to try to find the fans who yelled at him. Reporters later said the insults came from a group of three or four Mogi Mirim fans.
Brazil has been making headlines for the wrong reasons as it tries to get ready for the World Cup. In addition to problems finishing stadiums and infrastructure work, the country has been dealing with several cases of fan violence and court disputes that threaten to delay this year's Brazilian league because of a controversial sports tribunal decision that altered the results of last year's tournament.
"We can't let something like this happen, especially with the World Cup just around the corner," Santos coach Oswaldo de Oliveira said after the insults to Arouca. "These people need to be punished."
Police officials said they would try to find the fans responsible. Mogi Mirim president Rivaldo, a former star midfielder for Brazil, said the club was already looking at the stadium's security cameras to try to find out what happened.
"I'm against these kinds of attitudes from people who are not respectful to each other," Rivaldo said on Twitter. "We are all equal."
He said he was against any punishment to the club because "we can't control the fans' mouths."
On Wednesday, referee Marcio Chagas da Silva said some fans called him "monkey" and told him to "return to the jungle" before a match in the Rio Grande do Sul state championship. He said his car was vandalized and bananas were left on top of it.
"Unfortunately, this type of attitude is still happening in this country," Silva said.
Last month, Brazilian President Dilma Rousseff gave her support to a black Brazilian player who was taunted with monkey chants every time he touched the ball during a Copa Libertadores match in Peru. On her Twitter feed, Rousseff called the case involving Cruzeiro player Tinga "sad," adding that "sports can never serve as a stage for prejudice."
Racist behaviour is a longstanding problem at matches in Europe. FIFA has sponsored anti-racism campaigns that have had modest levels of success, and it has promised to raise more awareness during this year's World Cup.
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