Zenit St Petersburg's largest supporters group has demanded the club not buy black or gay players.
Russian Premier League champions Zenit have an inherent problem with racism and the latest flashpoint comes after one supporter waved a banana at Roberto Carlos earlier this year.
Despite the signing of Alex Witsel, of French Caribbean heritage, Zenit are the only major Russian team to have never signed a player of African heritage.
So synonymous has Zenit become with racism some black players are fearful of joining the club. It was reported France international Yann M'Vila received death threats when he was linked to the club.
"We're not racists but we see the absence of black players at Zenit as an important tradition," Zenit fan club Landscrona said in a letter.
Witsel signed from Benfica in the summer
"It would allow Zenit to maintain the national identity of the club, which is the symbol of St Petersburg."
The group also aired its qualms about "sexual minorities" playing for the club.
"We only want players from other brotherly Slav nations, such as Ukraine and Belarus as well as from the Baltic states and Scandinavia. We have the same mentality and historical and cultural background as these nations."
The letter, called the "Selection 12 manifesto", was posted on Landscrona's website on Monday. One of the most notorious mottos of the Zenit club ultras is 'There’s no black in the colors of Zenit'.
Former manager Dick Advocaat said in 2008: "I would be happy to sign anyone, but the fans don't like black players."
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