Alvaro Morata started his run 18 yards from goal and launched into the air as the cross arrived from the other side of the field. He buried the header for a goal back in September, his third of the season for Chelsea, and landed to cheers that rattled the English Premier League for weeks.

“Alvaro, oh, Alvaro, oh,” sang the Chelsea fans who traveled to North London for the away match against Tottenham Hotspur. “He came from Real Madrid, he hates the f***ing Yids.”

Chelsea supporters have long hurled anti-Semitic pejoratives at their rival, Tottenham, whose fan base has long had a sizable Jewish contingent.

Chelsea officials quickly distanced the club from the chant and threatened anyone caught making such remarks would be banned from future matches.

Earlier this month, players and coaches joined a Holocaust memorial initiative with the World Jewish Congress to declare, “We Remember.” International Holocaust Memorial Day is Saturday.

But the demonstration comes at a time when discrimination remains prevalent in soccer around the world, notably in international matches and in European club leagues.

FARE Network (formerly Football Against Racism in Europe), a nonprofit that studies discrimination in soccer, analyzed 1,378 soccer matches during the 2015-16 and 2016-2017 seasons and recorded 539 incidents of racist, anti-Semitic, homophobic, nationalist and Islamophobic nature, according the group’s monthly reports.

FARE reports disturbances to appropriate disciplinary bodies, such as national leagues, UEFA and FIFA.

Those incidents, compiled by 240 trained match observers worldwide and through media reports, show consistent race-, faith- and sexuality-based abuse at soccer matches around the globe.

“When the general politics in Europe are getting more and more right wing and racist, you can expect to see more racism in football,” FARE Development Officer Pavel Klymenko said. “Look at Donald Trump in the U.S. That convinces people that it’s okay to say things they wouldn’t normally say. We shouldn’t be surprised that this is happening.”

The group observed the most disturbances in the UK, Spain, Brazil, Croatia and Italy. Each country has a thriving professional league and competes well internationally.

Racism among fans remains a consistent scourge year after year. Right-wing and ultranationalist politics are often a part of the identity of a team’s most vocal and provocative fans, commonly known as “ultras.”

Race-based abuse ticked up 21.8 percent between the two seasons, a phenomenon Klymenko attributed to the deepening migrant crisis in Europe.

That’s led in part to a slowdown in anti-Semitic incidents, Klymenko said, since discrimination events often follow political trends.

But anti-Semitic and neo-fascist displays are sometimes difficult to detect. Ultra groups change gestures or symbols based on enforcement procedures. For example, when Spanish clubs cracked down on swastika displays after one was mowed into a pitch in 2015, ultras started using Celtic crosses to games and pledged allegiance to the Greek “Golden Dawn” political party, a neo-Nazi group.

In the Americas, homophobic and transphobic rhetoric is on the rise, Klymenko said. Such incidents spiked during the 2016-17 season, up 136 percent, according to FARE data.

Per rules of FIFA, soccer’s world governing body, clubs are punished on a three-tier system for discriminatory behavior at games. Officials close a portion of the stadium where an incident occurred first, then fine the club and close the entire stadium for subsequent matches if the behavior continues.

Finally, officials can shutter a stadium to fans for an extended period of time and dock points from teams to hurt their standings.

FIFA leaves enforcement of these rules to each league.

Those punishments work, Klymenko said. Fans eventually put the love of their team ahead of their offensive mannerisms, and teams start disavowing discriminatory fan groups.

“When the system is in place, it works,” he said. “The fans and the club understand. The clubs are saying it won’t be tolerated. The fans are changing their behavior.”

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