Since the 1970s, Major League Baseball clubs have generally added more and more minor league affiliates. In 1979, there were an average of 4.7 affiliates per major league club. This season there are 8.2 — a total of 245 minor league affiliates, the most since 1948, spread across 30 major league organizations.

But the Houston Astros, a model of modern player development, bucked that trend a few years ago. After the 2017 season, they reduced their affiliate count from nine to seven clubs. The Astros believed they could become a more efficient producer of talent with fewer farm clubs.

“For the baseball people, it was a feeling that it was better to concentrate the coaching resources. We were trying to support a bunch of players that had a less than one percent chance of making the major leagues,” said an ex-Astros official whose current team didn’t grant him permission to speak to us.

The Astros felt comfortable cutting the teams in part because of data harvested from new tech. Since turning over the vast majority of their player development staff and minor league coaches under GM Jeffrey Luhnow, the Astros feel they have become better at identifying which players have a chance to rise through their system. For example, while a number of teams were experimenting with their first high-speed cameras this spring to study pitch grips and body mechanics, the Astros had 75 such cameras hard-mounted at stadiums throughout their minor league affiliates last season. According to the ex-Astros official, the team believes it needs less time and fewer games to understand potential, and it is better served by consolidating resources around their most promising players.

The Astros aren’t the only ones questioning the structure of the minor leagues in their organization. For decades, baseball has generally treated player development as a ladder. First comes Rookie ball, then multiple levels of Single-A ball leading up to Double-A, then Triple-A, then finally the majors. But recently some players — like young stars Juan Soto and Fernando Tatis Jr., and lesser talents like David Peralta and Rougned Odor — have skipped rungs. And they aren’t worse for it.

Is the highest level of the minors always necessary? Average ERA+ or OPS+ for first-year players by their highest minor league level before their MLB debut, for debuts between 2010 and May 20, 2019 Highest level number of Batters Avg. First Year OPS+ Avg. First Year Age AA or lower 32 99.0 22.2 AAA 327 90.9 23.8 Highest level number of Pitchers Avg. First Year ERA+ Avg. First Year Age AA or lower 38 118.6 23.3 AAA 221 101.9 24.4 Minimum playing time for first-year players included 50 innings pitched or 100 plate appearances. Some players were demoted from majors to a higher minor-league level during their first-year seasons. ERA+ is earned run average adjusted for year and ballpark. OPS+ is on-base plus slugging adjusted for year and ballpark. Source: Baseball-Reference.com

So if some players are good enough to skip the upper levels of the minors, perhaps minor league resources should be spent trying to identify and develop those players — and perhaps a few rungs of the ladder ought to be removed. A Baseball America study of the 1981-2010 drafts found that only 17.6 percent of drafted and signed players reached the majors, and only 9.8 percent produced 0.1 career wins above replacement, a minimal level of production. Perhaps optimized skill development requires fewer games, and thereby fewer players and teams.

A year before the closing of two affiliates, in March 2016, the Astros hired Jose Fernandez to be part of their sports science department. He had worked with pro soccer teams in Europe. European soccer giants have centralized training centers focused on building skills rather than a decentralized sprawl of affiliates. The Astros were curious how FC Barcelona developed its players. Barcelona’s “La Masia” — which translates to “Farm House” — is regarded as one of the breeding grounds for talent. The information Fernandez shared was eye-opening.

“On site in Barcelona, they have their whole development academy, from the little kids all the way up to the professional teams. They have one big campus. They do everything on-site. Everything is coordinated. Everyone is doing the same drills. Everyone was being measured with the same technology. That makes a ton of sense,” the ex-Astros front official said.

While minor league baseball reorganized in 1963 to the classifications we are familiar with today (Single-A, Double-A, etc), the idea of affiliated minor-league baseball has fundamentally remained the same since Branch Rickey bought a stake in the Houston Buffaloes in 1919 and began building the first farm system. As Kyle Boddy, who runs the independent training facility Driveline Baseball, put it in my book, “The MVP Machine”: “Why is the minor-league system set up the way it is? Why does every coaching staff and player development staff feature the same titles, the same backgrounds and are approximately the same size? Why for so long has the minor league system been immune from disruption?”

MLB’s approach to the minor leagues is ripe for change in part because of how much data can be collected off the field these days. Independent hitting instructor Doug Latta tells his clients that they “don’t need much space to get better,” as improving via reps, video analysis and ball-tracking tech lessens the need for a player to play in regulation games. Latta worked with Marlon Byrd, Justin Turner and Hunter Pence in various storage-like facilities just before they changed their approach at the plate and improved their performance. Cody Bellinger was already a good major league player but became great this season after he changed his swing in similar modest spaces last winter. While batting cages have existed since Rickey invented them, they’ve never been the feedback machines they are today when outfitted with ball-, bat- and body-tracking tech.

On the pitching side, it’s perhaps even easier to gain skills. Adam Ottavino designed a new cutter last winter in a vacant Manhattan storefront that he outfitted with baseball’s cutting-edge tech. The Los Angeles Dodgers held several low-value minor league pitchers back from minor league games in 2016, giving them something of an extended spring training at their complex to see if they could improve throwing velocity. Dodgers pitchers Corey Copping and Andrew Istler learned how to throw harder and subsequently became trade chips last summer.

Author Daniel Coyle has written about the benefits of shrinking training space — like Brazil’s futbol de salao (indoor soccer) — to increase reps and feedback. “How do you tighten the [feedback] loop, and deliver the right signal in a timely way?”

This past winter, the Philadelphia Phillies tried to become more like the Astros, rethinking how they teach and train in the minor leagues. Two progessive hitting instructors were asked to implement new ideas, new programs and new technology for the 100-plus minor league hitters in the system, tailoring individual plans for each. They have transformed batting cages at each facility into feedback labs. Phillies minor leaguers in A- and Rookie-ball are required to wear sensors on their bats to record bat speed, bat path and biomechanical data. The Phillies also set up a device to track every ball hit in every batting practice before every minor league game. For decades, box scores were the only sources of data on player progress. But now practice is producing more data than games.

“The game is the ultimate test but that’s only three or four at-bats a night,” Russ Steinhorn, one of those progressive hitting instructors, said. “The practice before games, you might be taking hundreds of swings. … For me, the practice environment, the lead-up to the game, is the most important. That’s where the development happens.”

While there are rules on how players are assigned to teams, the ex-Astros official suspects we could see fewer affiliates one day and more time spent at facilities. “I think down the road in a few years you will see a guy go to an affiliate and play for a while and the team says, ‘OK, you’ve demonstrated that what you mastered at the training facility is working in games. So now it’s time for you to add a changeup.’ So it’s back to the training facility.”

Still, Seattle outfielder Mitch Haniger — who has worked with Latta and hitting coach Craig Wallenbrock to improve his swing — says minor league games will never be replicated despite whatever gains are made in technology.

“You can’t really simulate facing a pitcher in front of thousands of people,” Haniger says, “and failing in front of a whole bunch of people.”

On a late May afternoon in Erie, Pennsylvania, the Erie Sea Wolves — the Double-A affiliate of the Detroit Tigers — hosted the Bowie Bay Sox. A light fog rolled in off the lake, UPMC Park was perhaps at half capacity. While minor league baseball remains popular and big business for big-drawing clubs like the Columbus (Ohio) Clippers and Lehigh Valley (Pennsylvania) Iron Pigs, minor league attendance declined last season for the first time in 14 years last season and by 1.38 million fans. Erie is averaging 3,315 fans this year, 10th out of 12 clubs in the league.

Top prospect Casey Mize, the No. 1 overall pick in 2018, pitched that day like he was ready to fit in the Tigers rotation. He tossed eight shutout innings on 89 pitches.

Speaking afterward in a cramped, dated and faux wood-paneled clubhouse, where the players consumed postgame meals on card tables before their lockers, Mize seemed ready for another challenge. When asked about the practice of aggressively promoting players upward, Mize said, “I think failure is part of it and needs to be part of it. I see positives in being forced to fail.”

Some influencers of modern skill-building suggest that athletes ought to push themselves through practices like weighted-ball training — called overload training — to hasten development. To increase skill, take on more than you’re used to and the body adapts and skills improve. But how does that translate to games? In the NBA and NFL, top amateur players get thrown straight into the fray against top professionals. In baseball, top prospects spend years against lesser competition. How do you improve against inferior players?

“Major league [prospects] are seeing a lot of competition that is not helping them,” the ex-Astros official said. Because of this idea that players are feasting on lesser talent, minor league numbers can distort evaluation.

All-Star pitcher Walker Buehler has been part of cutting-edge training techniques with the Los Angeles Dodgers and when pitching for Vanderbilt University. While much has been said of the low pay and financial struggles of minor-league players in recent years, Buehler thinks there’s another problem: There are too many players that aren’t MLB-quality in the minors.

“At any affiliate, there are three players who have a chance to play in the majors. The rest of the players are there so they so they can play. I don’t think that’s fair,” Buehler told FiveThirtyEight. “You are preying on their dreams.”

Rethinking the minor leagues is being discussed at the highest levels of the sport.

MLB commissioner Rob Manfred told The Athletic in July that “we have to look at the efficiency of the [minor league] system that we’re running right now, how many teams, how many players, what we’re paying players, and all those issues are obviously related.”

What that means for the future of the farm system suggests it could, and perhaps should, look much different than it does today.