Ahead of Liverpool’s trip to St. Petersburg on Thursday, where the Reds will play Russian champion Zenit in the first-leg of its Europa League Round of 32 tie, Liverpool managing director Ian Ayre pinpointed Zenit’s recent racism problems as a “major concern.” In a manifesto published in December, a group of Zenit fans called the “Landskrona,” urged the club not to sign black, South American or gay players, saying that the lack of black players and “sexual minorities” is important to the club’s identity.

The troubling manifesto prompted Ayre to write to both UEFA and Zenit management expressing Liverpool’s concerns about its players and fans traveling to St Petersburg. He said the club would brief its players about how to react in the event of racism. “The most important thing for our players is that they remain professional throughout this,” Ayre said. “We certainly won't tolerate that type of attitude or any of those types of incidents from our team.” As for the club’s traveling supporters, he said they would be issued with guidance on what to expect and how to behave.

Zenit was the only Russian Premier League team without a black player until it signed Brazilian forward Hulk and the Belgian midfielder Axel Witsel this summer.