Rotund, bespectacled, and with an encyclopedic mind that has earned him the nickname "the Professor," Amir Khustuldinov is about as far as you can get from the stereotypical image of a football lout.
Yet Khustuldinov, 50, a native of Moscow and lifelong supporter of the city's Spartak football club, is also probably one of the most respected figures in the secretive and violent world of Russian football hooliganism.
"I started in 1977 when I was 12 and my dad started taking me to Spartak matches," he said at Spartak's north Moscow training ground. "I only quit because it's not very seemly for an old bloke like me to be fighting alongside youngsters and doing it better than them," he laughed.
A ruthless police crackdown in recent years has made terrace violence of the kind seen in France during Euro 2016 a rarity in Russia. Nonetheless, hooliganism in Russia remains a thriving underground scene.
"Football hooligans are ordinary people who love violence. And we are the most honest part of society. We don't deny that people aren't angels - we recognise that. We have business people, clerks, rightists, leftists, everyone. When your mates are at your back, and the other side is coming at you, and it's 'let's go!' - the world is in your hands. Neither sex, nor any drug, comes anywhere close to the adrenalin pouring through you after a fight."
Russia's football fanatic culture is generally agreed to have started in 1972. Terrace violence was occurring regularly by the 1980s.
By the mid-1990s, hooligans began to form into organised gangs, or firms. Three violent groups that emerged around Spartak from 1994 - Flint's Crew, the Gladiators Crew, and the Mad Butchers - were soon met by opposition such as CSKA Moscow's Red Blue Warriors. Soon, similar gangs were forming around clubs across the country.
While Khustuldinov insists that politics are banned from stadiums, he admits he and many others in the movement hold "quite right-wing" views that chime closely with those of the Kremlin. He sees the global West as guilty of unprovoked aggression against Russia. He supports the separatist movement in east Ukraine, but repeats the Kremlin's (long debunked) line that there is "no proof" of Russian involvement in the war there.
And he harbours a veneration for World War II as the foundation of Russian exceptionalism - the nearest thing Russia has to an official state ideology.