Most of the boxing fans who filled up Madison Square Garden on Saturday night were hoping to see a great fight, even if they weren’t expecting a competitive one. The main attraction was Gennady Gennadyevich Golovkin, known as Triple G, an astonishingly accomplished middleweight from Karaganda, Kazakhstan. Golovkin is an affable destroyer. He attained the status of cult hero immediately upon making his U.S. début, in 2012, and he has spent the years since trying, with some success, to de-cult himself. On Saturday, the popularity and ubiquity of “GGG” merchandise provided proof of the progress he has made: he had the home-crowd advantage despite the fact that his opponent, Daniel Jacobs, is a Brooklynite and an accomplished fighter himself. Most experts considered these the two best middleweights in the world, though few considered them evenly matched. Golovkin was as much as an eight-to-one favorite, and when The Ring polled twenty-two boxing experts, it couldn’t find a single one who expected Jacobs to win.

Golovkin’s boxing style is deceptive, and seductive. He fights carefully, patiently exploring his opponent, prodding for unguarded angles. But he punches with unaccountable power. His shots often look innocuous, at first, until you notice that the fighter on the receiving end has suddenly become too heavy for his legs. Golovkin entered Madison Square Garden not only undefeated but dominantly so, having won his twenty-three previous fights by some form of knockout. His biggest challenge had been the paucity of top opponents willing to fight him. Saúl (Canelo) Álvarez, a Mexican star and Golovkin’s biggest potential opponent, has discovered a number of reasons to stay out of Golovkin’s path. When Jacobs agreed to fight, fans were thrilled because Golovkin would finally get a chance to add an impressive name to his long list of victims.

No doubt this focus on Golovkin felt unfair to Jacobs, who has a compelling story (he is a cancer survivor), and who pulled off one of the greatest beatdowns in Brooklyn boxing history when, in late 2015, he dispatched a top rival with a first-round knockout. But, in boxing, domination often sells better than competition. Part of what fans grew to love about Golovkin’s fights was their brutal predictability—time after time, his opponents stopped fighting before the fight was over. Saturday’s fight was promoted as a chance to see one of the best boxers of the current age deliver perhaps the performance of his life. Jacobs, despite the excellence of his resumé, had previously been knocked down and, in another fight, stopped; it wasn’t hard to picture him crumpling under one of Golovkin’s well-aimed barrages.

Things started softly, with a three-round preface: Golovkin stalked Jacobs with his fists up, as predatory as a portrait photographer, trying to create the perfect frame for the perfect shot. Jacobs surprised him a couple times by punching back, and sharply. Then, in the fourth round, it seemed like Golovkin’s fans would get what they had paid for: Golovkin trapped Jacobs against the ropes and hit him with an efficient jab and straight right hand. Jacobs dropped to his backside and then stood up, and the fans roared in anticipation of a fourth-round knockout.

But Jacobs fought on. Because Golovkin’s punches are often harder than they look, it is tempting to give him the benefit of the doubt. Every time he made contact, people moaned in appreciation and sympathy. But, by the sixth round, when a fight in the balcony briefly overshadowed the intermittent fighting in the ring, it seemed that Golovkin’s punches were forceful, though not deceptively so. Even more surprising was what Jacobs was doing in response. He was tricky, switching between orthodox and southpaw stances, moving enough to keep Golovkin uncomfortable. (“The game plan was, just confuse him,” Jacobs said, after the fight.) Jacobs’s fans in the arena were getting louder—and, perhaps, more numerous, too. At a boxing match, rooting interests tend to be strong, but not necessarily fixed; as Jacobs refused to wilt, and Golovkin began to look somewhat tired and frustrated, some of the spectators felt a sudden infusion of civic and national pride. Who did this guy from Kazakhstan think he was?

More to the point, who did we think he was? Golovkin fought well, or better than well, exchanging punches with a top middleweight who was putting on the performance of his life. Jacobs became the first boxer to take Golovkin into—and then through—the twelfth round. The final bell rang, which meant that three judges would need to make sense of the encounter.

Twelve rounds, leading to a decision about which reasonable boxing fans (if any such people exist) might disagree: this, alone, counted as a kind of upset victory for Jacobs. But Jacobs, reasonably enough, wanted an actual victory, too. He didn’t get it. One judge gave the boxers six rounds apiece, and the other two gave seven of them to Golovkin. When the knockdown, which was worth an extra point, was taken into account, Golovkin was declared the winner by unanimous decision. And then another first: the affable destroyer from Kazakhstan, having failed to provide the destruction that fans expected—having provided, instead, a tense and surprisingly competitive fight—was loudly booed. During his post-fight interview, Jacobs suggested that Golovkin’s victory was evidence of corruption, part of a plan to set up the lucrative and long-awaited match between Golovkin and Álvarez. On Twitter, Jacobs declared, “I clearly won.”

Officially, at least, Triple G is still the best middleweight in the world, and, some will insist, the best boxer, period. (Golovkin’s claim on this latter title was helped earlier in the night, when a brilliant Nicaraguan junior bantamweight named Román (Chocolatito) González lost an even more controversial, and quite likely erroneous, decision; many had previously considered González the pound-for-pound champion.) But Golovkin has a rival now, and a changed identity. Next month, he turns thirty-five, which means he is probably slowing down. After the fight, Golovkin’s trainer, Abel Sanchez, paid tribute to Jacobs, and offered an alternative explanation for Golovkin’s strong but non-dominant performance: “I just think the opposition’s getting better,” he said. In the ring after the decision, Jacobs remembered being knocked down, getting up, and thinking, “This is all that he had?” In the end, Golovkin had enough to win, and, in nearly every sport except this one, that would be plenty.