At Madison Square Garden on Saturday night, eager (and perhaps not entirely sober) fans could, if they wanted, spend three hundred dollars on a bright red warmup suit branded with the name of the most famous athlete in the history of Kazakhstan. It was, to be fair, an impressive-looking suit, although what was more impressive was the way the suits disappeared from the merchandise stands as the night wore on, along with white T-shirts priced at sixty dollars and emblazoned with the athlete’s sponsors. These names seemed, in an arena typically ruled by familiar brands, refreshingly exotic: BI Group, Stada Pharmaceuticals, Tsesnabank.

The occasion was the biggest fight so far in the phenomenal career of Gennady Gennadyevich Golovkin, known as G.G.G. (or, as it’s pronounced, Triple G), an unbeaten and seemingly unbeatable boxer from Kazakhstan. He fights as a middleweight, a hundred and sixty pounds, demolishing opponents and then grinning about it, looking less like a sadist and more like a good-natured guy delighted to discover, anew, that he can entertain crowds simply by doing something that comes naturally to him. Saturday’s crowd included plenty of Kazakhs, some of whom were enshawled in their country’s elegant flag, which imposes a golden eagle and sun on top of a sky-blue background. Some other attendees had their faces painted with darker blue bars, representing the Nicaraguan flag, because Román González, a similarly great Nicaraguan boxer, was also on the bill. González is a miniature leviathan terrorizing the flyweight division, where the limit is a hundred and twelve pounds. But many of the fans seemed to be rooting not for a country but for a sport: they were boxing connoisseurs, drawn by the opportunity to see a couple of masters at work.

Last month, Floyd Mayweather, Jr., announced his retirement; he was widely considered the best boxer in the world, and now fans are trying to identify his replacement. If dominance is the criterion, then the most deserving fighter might be Wladimir Klitschko, the bruising Ukrainian heavyweight, who hasn’t lost in more than a decade. But the current crop of heavyweights is considered weak, and many of Klitschko’s victims have been undistinguished; those who value achievement might instead favor González, the Nicaraguan, who prevails in a more talented division. (ESPN.com officially deems González the best fighter in the world, although its senior boxing writer, Dan Rafael, thinks that title should go to Klitschko.) Another approach is the so-called eyeball test, a highly scientific approach in which the bragging rights go to whatever fighter looks the most impressive. Using this approach, Golovkin may be worthy: he looks as if he could beat anybody, even though he hasn’t yet beaten anybody very special.

On Saturday night, González may have had the tougher challenge: he was fighting a sturdy and accomplished opponent named Brian Viloria. As it happens, they possess two of the sport’s best nicknames. González is known as Chocolatito, because he is dark-skinned, like his father, who also boxed, and who was known as Chocolate. Viloria, who was born in Hawaii, calls himself the Hawaiian Punch. Although Viloria never stopped punching and sometimes connecting, González battered him until his face started to swell; the referee’s stoppage, in the ninth round, seemed not at all too early, although Viloria said, as boxers are supposed to, that he would have liked to keep fighting.

Golovkin’s opponent was a skilled but not extraordinary Canadian named David Lemieux, and the night seemed designed less to test Golovkin’s boxing ability than to test his commercial appeal. He has been deemed more marketable than González: bigger, and therefore scarier, but also smilier, and therefore more lovable. The fight was broadcast on pay-per-view at a price of as much as sixty dollars; this was Golovkin’s first time as the main attraction in a pay-per-view fight. In the next few weeks, as we begin to get reports of how many people bought the fight, we will have a way to measure the size of his cult, and the distance between him and an established pay-per-view star like Manny Pacquiao. At the Garden, the fight was a sellout, but a relatively soft one: as of Friday, tickets were available on the secondary market for as little as ten dollars, plus fees; for a solitary boxing fan in the city, it would have been cheaper to sit in the bleachers than to watch from home.

Sometimes the main advantage of seeing a fight in person is aural, not visual. On Saturday, the memorable noises included not only the expected roar when Golovkin emerged, grinning, in his embroidered robe, but also the boisterous booing that arose when it was announced that one of the celebrities in attendance was Donald Trump, who paid a friendly pre-fight visit to Golovkin in his locker room. At times, it was easy to imagine Golovkin as an unlikely crossover success, following in the footsteps of Pacquiao, who has become not only a Filipino hero but also an American celebrity. (Golovkin recently moved to Los Angeles, and he has courted the region’s many Latino fans; on Saturday, two men in the crowd were wearing matching “Mexicans for Golovkin” T-shirts, which were sadly absent from the merchandise stalls.) And, at times, the event seemed like yet more proof of boxing’s niche status: while much of the city was following the Mets’ first game against the Cubs, thousands of cultists had chosen instead to spend their Saturday nights pledging allegiance to a boxer who is a household name only in a country that is surely not, itself, in many American homes, a household name.

Golovkin didn’t provide his fans the kind of sublime or grotesque finish that they will be able to brag about having seen in person for years to come. (Attendees in search of brutality got some, earlier in the night, when a rising heavyweight named Luis Ortiz sent his overmatched opponent, Matias Ariel Vidondo, flopping face-first into the mat; as the ring filled up with functionaries, Vidondo arose, pressing his eyes shut and shouting, “I’m all right! I’m all right!”) On this night, Golovkin was surgical from the start, jouncing Lemieux’s head backward with an accurate left jab that probably would have looked dramatic even if not for Lemieux’s hair, shaved on the sides and long on the top, which whipped around every time that Golovkin made contact.

Everyone knew that Golovkin was a better boxer, but some observers thought that Lemieux, a hard puncher, had a slim but real chance to catch Golovkin and stun him. (One oddsmaker installed Golovkin as a sixteen-to-one favorite, with Lemieux as an eight-to-one underdog.) The other, more prescient theory of the fight was that Lemieux was chosen not because he would be competitive but because he would be brave—unwilling to run, and willing to withstand Golovkin’s punches long enough to give fans their money’s worth. In the fifth round, Golovkin coiled a left hook into Lemieux’s ribs, sending Lemieux to his knees, as if in reverence. In the eighth round, after yet another barrage, Lemieux grimaced, staggered backward, and tilted forward, which gave the referee the excuse he needed to restrain Golovkin, making him the winner by technical knockout. Golovkin’s victories tend to be decisive: it has been seven years, or twenty-one fights, since last he allowed the ringside judges to complete their scorecards.