But what about the home team? Will fantasy sports usurp the real thing? Illustration by Nishant Choksi

In the fall of 1979, while on a flight from Hartford to Austin, the writer Daniel Okrent was struck by an idea for conducting an auction of baseball players—or, rather, baseball players’ names and their future statistics. Nothing fancy: this was before the spread of personal computers and sabermetrics. His notion was that, using only the stats that could be tallied or figured from the box scores in the morning paper, you could approximate the potency of a virtual team, compare it against other virtual teams, and thereby imagine yourself as a real-life general manager in training. “It was because I was a shitty athlete,” he recalled recently. Fantasizing about what it would be like to play third base was too implausible. In Austin, he accompanied a few editors and writers from Texas Monthly to a barbecue joint, where he revealed the outlines of his new scheme. They weren’t interested. Fall gave way to winter. Okrent mentioned the idea to some friends over lunch at a French restaurant in Manhattan, and this time it took. Instead of Brisket League Baseball, we got Rotisserie, named after La Rotisserie Française, a long-vanished eatery on East Fifty-second Street.

The entry fee for the initial ten-team Rotisserie League, in 1980, was two hundred and fifty dollars, and the winner, at season’s end, would collect half of the over-all pot. Okrent feared that this might make them gamblers—personae non gratae—in the eyes of the sport’s custodians. He was planning to write a book, later published as “Nine Innings,” that would be a micro-examination of a single baseball game, between the Milwaukee Brewers and the Baltimore Orioles. The project required extensive clubhouse access. To be safe, they confined their Rotisserie auction to players from the National League, rendering the Brewers and Orioles irrelevant. “A guy I came to know in the American League president’s office said it was absolutely the right thing to do,” Okrent said. “You know the moralism they’ve always brought to the very idea of gambling.”

There was another virtue to the National League restriction. Okrent had grown up a fan of the Detroit Tigers, in the A.L., and he worried about the potential for conflicting loyalties—not just overpaying for the Tigers’ ace Jack Morris, say, out of wishful thinking, but depending on some of the Tigers’ best-known adversaries for the success of the Okrent Fenokees, as he called his squad. The childish simplicity of sports rooting had always seemed one of fandom’s greatest virtues, and he was grateful to be able to separate watching the Tigers from managing the Fenokees.

The other founding Rotisserians, like Okrent, were well connected—writers, editors, academics—and word of their new pastime spread quickly, attracting imitators. Within a few years, baseball officials had a genuine nuisance on their hands: “the number of people calling the P.R. department and pretending to be journalists, asking whether the pitcher’s arm was still hurt,” as Okrent put it. Those callers weren’t gamblers, either; they were Okrent’s proliferating disciples, looking for inside intel to exploit on the virtual trading block.

Card-based simulations, like Strat-O-Matic, which now boasts of producing “the original fantasy sports games,” had existed since the nineteen-sixties, but they relied exclusively on past events and didn’t flatter the sports fan’s unshakable sense of clairvoyance. Strat-O-Matic contests were truly imaginary. Rotisserie was grounded in reality. Actual human beings were affirming (or disproving) your hunches and investments in real time. Okrent and company trademarked the name Rotisserie (thus giving birth to “fantasy” as a generic alternative), began publishing guidebooks, and even hosted conventions during spring training. “People would come from around the country to stay at the Belleview Biltmore Hotel, in Clearwater, and spend time with us,” Okrent recalled. “Very creepy. They were not people you’d want to take home.” What he meant, in essence, was that the expanding audience was not composed of intellectuals, like the pioneers, but standard-issue geeks, who had embraced their new hobby with a Dungeons & Dragons-like fervor. By the early nineties, when I was in high school, the concept had proved durable—and flexible—enough that a few seniors were playing what they called Rotisserie Cross Country, using the running times of gangly sixteen-year-olds in Bergen County, New Jersey, as fodder for study-hall competitions.

By the late nineties, with the arrival of the Internet, the concept had spread to football and had spawned a full-blown industry, with an official lobbying arm—the Fantasy Sports Trade Association. The F.S.T.A. created a Fantasy Sports Hall of Fame and honored Okrent and his friend Glen Waggoner, another writer and the winner of the first-ever Rotisserie crown, back in 1980, as its inaugural inductees. “You couldn’t have paid me to go,” Okrent said of the ceremony, which took place in Orlando. He had by then become disillusioned with his billion-dollar creation, for which, he now estimates, he and his fellow-founders have each banked “maybe ten thousand dollars, fifteen thousand dollars, something like that,” for all their prescience.

He had also temporarily shuttered the Okrent Fenokees, who never did win a championship, out of fantasy fatigue. “In the first year or two you’re playing, you are much more engaged with baseball than you’ve been since you were seven years old,” Okrent said. “And then, by your fourth or fifth year, the actual game has lost meaning for you. You’re engaged in the numbers that the game spins out and engaged with millions of others in the same way. It has no relationship not just to the fan attachment that you may have had to a particular team but to the physical thing that’s taking place on the field. It’s the representation of it in a number that’s what’s important. I’m thinking of our original group. A couple of them really don’t give a shit about baseball at all anymore.” He added, “When people say, ‘How do you feel, having invented this?’ I say, ‘I feel the way that J. Robert Oppenheimer felt having invented the atomic bomb.’ I really do. I mean, pretty terrible!”

A couple of months ago, I attended the winter conference of the F.S.T.A., in Las Vegas, and detected an air of triumphant ascendancy, as though the future of sports itself lay in the hands—or in the obsessive brains—of the nearly four hundred people swapping waiver-wire strategies and business cards at the Bellagio. After years of being dismissed as a lesser breed of sports fan, the fantasy crowd had proved its strength in numbers: some forty million participants in North America, including eight million women. More important, though, was the belated embrace of the professional teams and leagues, which had initially sought to distance themselves from an activity that seemed so transparently parasitic. In the Internet age, where enthusiasm and loyalty can be measured in terms of media minutes consumed, the best kind of customer is not the polymath with a wry disposition and an ability to charm the in-laws but, rather, a junkie. Primordial sports fans, content to watch athletics as theatre, devote a mere six hours a week, on average, to the consideration of balls and pucks. Fantasy nerds do triple that. And then there are people like Jeremy Munter.

Munter, a.k.a. Muntradamus, is a lanky and slightly manic twenty-seven-year-old who moved to Las Vegas a couple of years ago so that he could “be in my own cloud, my own zone,” as he told me, “and not answer to anyone and just focus on dominating fantasy sports.” The genre of fantasy sports that he is intent on dominating bears only a vestigial relationship to Okrent’s original idea. Instead of joining leagues, among friends and colleagues, you participate in nationwide tournaments, some with tens of thousands of entrants—and, crucially, winners are crowned, and paid, just hours after you’ve created your team, on the basis of the players’ performances in an evening’s worth of games. With daily fantasy, as these contests are called, any odd Tuesday can be your Stanley Cup or your World Series, although the repeatable and impersonal nature of the format attracts a more compulsive clientele. Munter has been known to create two hundred teams in a night, at two dollars apiece, preferring a low-risk, high-volume approach, like a day trader. “First fifty teams I make, I won’t even do a spreadsheet,” he said. “I’ll look at the players and just know—like, K. J. McDaniels, that’s a good price for him. Tony Wroten, that’s a good price.” (The entrance fees are real, but the “salaries”—subject to a cap, just as in the N.B.A.—remain notional.)