Brad Mills / USA TODAY Sports / Reuters

Earlier this month, the little-known Atlantic League made news. In partnership with Major League Baseball, the independent minor league announced that it would be implementing a series of rule changes designed to “create more balls in play, defensive action, baserunning, and improve player safety.” In other words, the Atlantic League would become a testing ground for tweaks that might find their way to the majors, such as electronic home-plate umpires and moratoriums on mound visits. To baseball obsessives, these alterations surely seem sacrilegious. To some casual fans, they might scan as reasonable and even exciting.

The commissionership of Rob Manfred, which on Thursday will reach its fifth Opening Day, has largely been defined by a growing courtship of that latter group. Baseball’s future, the thinking goes, will be decided by an audience less willing than the one that came before it to endure five-hour Yankees–Red Sox marathons. In past years, Manfred’s adjustments to the sport have been minor, and his comments measured. He has shortened the time between innings and limited pitcher-catcher conferences. He has hoped for “an organic movement” away from the homer- and strikeout-heavy trends of recent seasons. But the trial runs in the Atlantic League, and the ongoing chatter about baseball’s 50-plus fanbase, suggest that more meaningful changes could be imminent. America’s most traditional sport is now fully subject to revision, and new seasons have begun to feel like focus groups.

The drawbacks of MLB as it exists today—or, at least, the drawbacks as understood by the league itself—are visible in the Atlantic League’s alterations. The notion that pitchers must face three batters, or reach the end of an inning, before they are removed addresses the fatigue that fans feel when waves of relievers prolong the ends of games. Requiring two infielders to be on each side of second base effectively eliminates the analytics-informed infield shifts that, over the past decade, have turned would-be hits into easy outs. The elimination of all mound visits, except in the case of injury or a pitching change, kills some measure of baseball’s ample downtime; ditto the between-innings break being cut down from two minutes and five seconds to a minute and 45 seconds. The most extreme change—moving the mound back by two feet—will go into effect only for the second half of the Atlantic League’s season, and it gestures toward a more fundamental concern for MLB officials. Maybe athletes have become too strong and too fast, and the strategies too airtight, for the parameters of the sport as they’ve existed for 50 years.

These rule changes—at least one of which will be adopted by the big leagues in 2020—help paint a picture of a generation of fans as envisioned by Manfred and his colleagues. These fans like action, abhor downtime, and find the long-ball-and-whiff parade of recent years repetitive. They’re willing to sacrifice some “no clock in baseball” romance for a snappier viewing experience. They aren’t as interested in the pursuit of optimal strategy as in stylistic variation. Launch-angle and spin-rate studies are fine, but balls in play are better.

The assumption is that the non-AARP set doesn’t have a problem with baseball; it has a problem with this kind of baseball, the drawn-out and hyper-strategized version of the 2010s. But there’s reason to doubt such a conclusion. Days after MLB’s Atlantic League announcement, the NBA released a “10-Minute Pass,” which allows fans to pay a dollar to stream a quick section of any team’s game. The timing was probably coincidental, but it nevertheless said something about the sport’s status as the preference of the American Millennial, that supposedly attention-span-deprived and smartphone-addicted demographic. A given 10-minute stretch of, say, Golden State Warriors basketball is a safe bet to produce some manner of spectacle, such as a Stephen Curry three-pointer or a Kevin Durant dunk. The same length of a Los Angeles Dodgers game, meanwhile, might yield only a couple of groundouts and a pitching change.

The simplest explanation is the one that MLB brass can’t publicly acknowledge: that it may be the sport itself, not some anomalous recent iteration of it, that doesn’t resonate like it used to. The question, then, is how far the league might go in its pursuit of a new generation of fans. “We think that a little focus on pace of game, while always respecting the tradition and history of the game, will always help us with the younger group,” Manfred said in 2017, and his pet project, the 20-second “pitch clock,” remains a possibility. But the further-out updates already being tinkered with suggest that aspects of that tradition and history are negotiable.

It is impossible to forecast exactly how baseball might change over the coming decades, though there are grounds for guessing. Automatic base runners in extra innings have been tried in the minor leagues, and robot umps have crossed the mind of any fan who’s seen his or her team suffer a bad call. Some initial changes, at least, might feel more retro than futuristic. The abolition of the infield shift and the minimum-batter requirement for relievers would move the game back toward the common (if not required) practices of decades past, when second basemen stayed in their spots and pitchers threw as long as they could.

Whatever the specifics, as the 2019 season gets under way, there is a growing sense that it could be one of the last to look like this. The cause is the same as ever in big-time entertainment: the pursuit of attention and money. The ultimate effect may or may not be what Manfred is after, but along the way, baseball’s attempt at modernization figures to narrow the scope of American sports. The slowest game will get faster; the game most resistant to change will get more experimental. “There’s no clock in baseball. And there’s no clock in baseball for a reason,” the Washington Nationals pitcher Max Scherzer griped when the subject was raised to him last month. He may be working under an old definition.

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