The MVP Machine: How Baseball's New Nonconformists Are Using Data to Build Better Players

by Ben Lindbergh

Naturally, the academy initiative was widely disparaged, both by some elements inside the organization and by rival teams. “Most clubs thought it was a waste of time, waste of money, wouldn’t work,” Stewart says. The Royals’ experiment ruffled even more feathers when the academy sent a team to the Gulf Coast League in 1971 to compete against rookie clubs from several other organizations. Even though seven of its twenty-eight members hadn’t played baseball in high school and the others had been passed over in the amateur draft, the academy team went 40–13, winning the league championship and stealing 103 bases, nearly double the next-speediest team’s total.

Boddy has a radical suggestion for how we should teach children intent. “Don’t ever play catch with a six-year-old,” he says. “I’d put my kid by a fence, and I’d throw the shit out of the ball into the fence, like as hard as possible.” That way, Boddy says, the child will learn and mimic an adult’s max-intent mechanics. Kids copy the adults they’re around, Boddy notes. Boddy’s theory on why the children of major leaguers succeed at such a high rate is not so much genetics—which doesn’t hurt—but because they’ve emulated more effective throwing and movement patterns. If you play catch, lightly, at low intent, kids learn the wrong motion, he says. “[Then] you yell at them at age twelve when they’re not athletic,” Boddy says. “But you just spent six years teaching them how to throw like an idiot, so what do you expect?” He had always intuitively believed that max-effort throwing helped pitchers throw harder, but professional baseball was moving in the opposite direction.

This process is rooted in the thinking of Aristotle, who called it reasoning by first principles. It was an idea instilled in Boddy as a child by his father, who worked for a time as an electrician for British Petroleum and at NASA’s Glenn Research Center when Boddy was growing up. Entrepreneur Elon Musk is also a proponent. During a TED Talk interview in 2016, Musk explained how his process of innovation begins by boiling “things down to their fundamental truths and reason[ing] up from there.”1 This method, Musk argued, is far superior to reasoning by analogy, “which essentially means copying what other people do with slight variations.” When Musk began researching how to build a rocket, he told Wired,2 he put aside conventional methods and approached the problem with a fresh perspective. “Physics teaches you to reason from first principles.… What is a rocket made of? Aerospace-grade aluminum alloys, plus some titanium, copper, and carbon fiber. And then I asked, what is the value of those materials on the commodity market? It turned out that the materials cost of a rocket was around 2 percent of the typical price.” SpaceX was born.

Throwing a heavier ball—say, seven ounces—increases total force. When the pitching arm is cocked back to begin the throwing motion, in maximum external rotation or lay back, the ball feels heavier. The body adapts to manage the greater total force. But overload training could also be paired with underload training in a complementary, two-pronged approach that could improve total force and peak force. The underload ball enables the arm to move much faster, creating a higher peak force that ultimately determines throwing velocity. Strengthening the body with heavier balls and greater total forces allows it to take on greater peak forces. To many instructors, overload training seemed inherently dangerous. Still, some, like Cressey, had challenged that assumption as early as 2009, when he noted that the weight of a baseball (five ounces) was three times lighter than that of a football (fifteen ounces) but that quarterbacks suffer far fewer arm and shoulder injuries than pitchers, despite possibly throwing even more often. A typical set of weighted baseballs ranges from three to eleven ounces.

Bauer’s and Boddy’s passion for technology brought them together. But their relationship deepened over another shared passion: the biomechanics of throwing. In 2013, his first season with the Indians, Bauer had grown concerned about pain he’d developed during the previous season with Arizona. Since then he’d been dealing with groin, back, ribs, and biceps pain and discomfort that he’d never experienced before. “It was very clear I needed to make a [mechanical] change if I was going to last ten years in the big leagues,” Bauer says. He had tried to mimic Lincecum, which was logical in that Bauer was also an undersized right-handed pitcher. But Bauer was well aware that in 2012, Lincecum had started to break down; he was finished as an above-average pitcher by age twenty-eight. “The long-term effects of moving that way and not being built muscularly or structurally to be able to handle that started piling up,” Bauer says. “I was on the same track [as Lincecum].”

Bauer had not intended to throw that day. But as Boddy spoke about possible solutions and drills, his words made so much sense that excitement surged within Bauer. He was wearing street clothes, including Nike Free running shoes. Nonetheless, he picked up a ball and took it to the mound. To improve his posture and add torque, Boddy told Bauer to hold a two-pound ball, an overload implement, in his glove hand and throw a pitch. The drill was designed to keep his glove side more elevated and his upper body back with less spinal tilt while his lower body moved forward. Boddy called the practice a “linear distraction.” The drill also forced his glove side to decelerate in the proper sequence because he was compelled to tuck the two-pound ball near his body as he began to throw, which increased his rotational velocity while keeping his head and body more in line with his target. He could feel the improvement immediately.

“Elevate and celebrate” and “Ground balls suck” became batting-cage cries. In 2018, Red Sox skipper Alex Cora said, “We don’t like hitting ground balls. We like hitting the ball in the air.” His statement mirrored a Cubs catchphrase—“There’s no slug on the ground”—

The camera helped Warren win a long-standing argument he’d had with his son. Trevor believed pitchers decided when to release pitches, but Warren didn’t believe this was a conscious action. The camera confirmed his suspicion. It showed that pitchers don’t release the ball by moving their fingers. Rather, the hand accelerates the ball linearly, forcing the fingers to extend or open. This led to a key finding that would shape Trevor’s future approach to pitch design: grips were best thought of as escape routes for the ball.

At Driveline in the winter of 2015–2016, Boddy used the video to help Bauer design a spin axis that would maintain a smooth spot at the front of the ball—uninterrupted by seams in its rotation—throughout its flight to the plate. Using the Edgertronic to provide constant feedback as he experimented with different grips, Bauer built a reasonable facsimile of Maddux’s comeback two-seamer. It was a remarkably short period in which to acquire a skill that would be effective at the highest level of sports. Boddy believes that such rapid pitch acquisition will become the new norm. “Unbeknownst to me, multiple hitting coaches saw that video and then saw us develop the two-seam fastball and were like, ‘That is why hitters could be fucked for basically the next ten years if they’re finding out new ways to move the baseball,’” Boddy says. “And that’s true.”

What Bauer wanted that off-season wasn’t just any slider, but the perfect slider: a pitch with zero vertical movement aside from the effect of gravity, but one that darted laterally away from right-handed batters and toward lefties. He hoped to attain ten inches of horizontal movement or break—an elite level. (In 2017, the Dodgers’ Yu Darvish led baseball with an average of nine inches.)

One day in the winter of 2016–2017, Bauer complained to Weathers about their weight-room workouts. “You think this is fun?” said Weathers in response, while adding weights to a bar. “I’d rather be home with my wife. You’re being a bitch.” The surest way to anger Bauer is to call him a bitch. He stormed out of the gym. Whenever someone called Bauer a bitch, he thought back to Lone Survivor, the book by former US Navy SEAL Marcus Luttrell, who suffered multiple gunshot wounds and a broken leg in a Taliban ambush in the mountains of Afghanistan. If Luttrell could survive that, Bauer could finish a workout.

“You cannot name a pitcher in the big leagues, or probably from Double-A and up, who is a worse athlete than Trevor,” Boddy says. “There is probably not a single person. He doesn’t belong in professional baseball. And that is an unbelievable story.” Boddy can say this objectively because he’s tested a wide range of professional players in his lab. He notes that Bauer has pathetic jumping and running ability. “His vertical is probably two standard deviations under a standard [pro] athlete and probably a standard deviation under an average man,” Boddy said. “He can barely jump twenty inches.” He has a slow arm and low testosterone. “He has a bad bod,” Boddy says. “It leads people to believe that he doesn’t lift weights, but that’s not true. He deadlifts 540 pounds and he benches 100-pound dumbbells. It just doesn’t matter because he has no testosterone so his body doesn’t change.”

Boddy adds that the idea that Bauer is some sort of eccentric genius is also off base. “He’s actually not that intelligent when it comes to analyzing stuff,” Boddy says. “To me, intelligence is picking up skills quickly. He’s really shitty at [that]. But he’s really good at brute-forcing things.… He doesn’t belong in the big leagues, but he’s there because he’s delusional. I wish that was the story that could go out there, but it’s not that popular. It sends kids a different message rather than ‘You can do anything.’” The message, Boddy suggests, is that achieving lofty ambitions requires maniacal obsession. “To me, that is true skill acquisition. He gets the most out of who he is.”

There’s another compelling case for promoting so-called secondary stuff. Recent research has shown that contrary to long-held beliefs about breaking balls inflicting the most stress on pitchers’ arms, fastballs actually do the most damage. “When you see there’s not a spike in injuries with guys throwing more secondary pitches—and in fact it might even be the opposite—it opens up this whole world of opportunities that was never there before, because people were afraid,” Bannister says. The unfounded bias against breaking balls, he adds, “prevented thousands of pitchers from pitching at a higher level.” One wonders how many Hill-like soft tossers fell by the wayside before teams had the tools to find them and the willingness to let them work in the ways that would benefit them the most. Without those things, Hill says, “you’ll never know the potential of the player.”

The late Seymour Sarason, Yale professor and father of the field of community psychology, unwittingly anticipated the problems impeding player development in one of his seminal studies of school reform, the 1971 book The Culture of the School and the Problem of Change. The conundrum, Sarason explained, is that “the agents of change from outside the school culture are too frequently ignorant of the culture in which the change is to be embedded, or if they are part of the culture, they are themselves victims of that very fact.” On one side of the process, the outsiders evince a “too frequent tendency to underestimate the complexity of the school system as a social system, and how this adversely affects what one hopes to accomplish.” Meanwhile, many members of the insider group “do not seek change or react enthusiastically to it.” That mutual ignorance polarizes relationships.

Before Bannister, the closest the statistical community had come to influencing a major-league pitcher’s performance was what came to be called the “Félix Incident.” In June 2007, future FanGraphs managing editor and Padres analyst Dave Cameron—then a full-time corporate cost analyst for Hanes and a part-time blogger for the Mariners site U.S.S. Mariner—posted “An Open Letter to Rafael Chaves,” the Mariners’ pitching coach. Cameron observed that the Mariners’ ultratalented but mercurial ace-in-waiting, Félix Hernández, was far too fastball-reliant early in games, and he pleaded with Chaves to make him mix it up. Soon after, a fan in the stands handed a printout of the post to Chaves. Chaves, who claimed that he’d already been trying to persuade Hernández to vary his pitch selection, relayed the post to the pitcher to prove that his pattern was well known. “Chaves gave me a report,” Hernández said in early July, after his second consecutive strong start. “On the Internet, they say when I throw a lot of fastballs in the first inning, they score a lot of runs. I tried to mix all my pitches in the first inning.”

In a November 2011 interview at FanGraphs, Bannister’s Kansas City pitching coach, Bob McClure, suggested that Bannister had committed a cardinal sin of old-school baseball: overthinking things. “Banny got a little overboard and tried to do more than he was capable of doing,” McClure said, adding, “He got into things like how the ball was turning, and to me, it’s not that complicated.” McClure, a pitching contemporary of Floyd’s, was a baseball lifer who harbored some reservations about the role of data; elsewhere in the interview, he spouted the age-old advice that had held back Hill: “Establish your fastball, if you can, to as many hitters as you can.” McClure became Boston’s (and Hill’s) pitching coach the next year but was fired in August, as the last-place team’s pitching staff posted the worst park-adjusted FIP in franchise history.

To play a part in pushing it forward, Bannister needed to know more. When he was with the Royals, Bannister had an accomplice in his pitching explorations: Zack Greinke. Like Bannister, Greinke saw pitching as a science experiment. In 2007, Bannister’s first season in Kansas City, Greinke recorded a 5.71 ERA through his first seven starts and was banished to the bullpen. There, Bannister says, Greinke learned that although he had great command, he didn’t need to nibble; he could get creative and blow batters way. At the end of the season, Greinke returned to the rotation for seven more starts and posted a 1.85 ERA, launching the peak of a Hall of Fame–caliber career. “We used to try to come up with the nastiest sequences Zack could throw,” Bannister says. One favorite from 2009 was the slowest curve Greinke could throw for a strike—something in the 60s—followed by an upper-90s fastball up and in to a righty, tunneled out of the same slot and often fouled off, and then a coup de grâce 90 mph slider down and away. “That three-pitch sequence alone took him to a Cy Young Award that year,” Bannister says. Greinke was worth 10.4 WAR in 2009, the highest pitcher total in the fifteen years following Randy Johnson’s fourth consecutive Cy in 2002. When he won the award himself, Greinke told the New York Times, “I’m also a follower, since Brian Bannister’s on our team, of sabermetric stuff and going into details of stats about what you can control,” adding, “That’s pretty much how I ...

Not only could Greinke easily outstrip Bannister’s loftiest radar readings, but when he and Bannister challenged each other to see who could throw the slowest curve for a strike, Greinke won that competition too. In 2009, he threw pitches at every mile-per-hour increment from 60 to 100.

Unlike Trevor Bauer and Kyle Boddy, Bannister isn’t brash; he doesn’t take Twitter potshots or call out coaches who don’t see things the same way. “My goal was always to be the most coachable guy on the team,” he says. Yet his studies drew him to the same conclusion: baseball was beset by beliefs that didn’t stand up to scrutiny in the more illuminating light of the post-PITCHf/x era. Right-handers have to throw from the third-base side of the rubber to maximize deception; pitchers should come to a balance point during their deliveries; changeups must be at least 10 mph slower than fastballs; pitchers need to pitch on downhill planes. “I’ve pretty much debunked all of those pitching concepts that are just rehashed over and over again to every pitching prospect that comes along,” Bannister says. “And I disagree with almost all of them completely.… I think those things, as innocent as they seem, have destroyed more pitchers’ careers over the years than anything else.”

As a former No. 1 pick, Floyd knows better than most that tampering with top prospects has historically been a career-jeopardizing proposition. “Most pitching coaches are fearful that if they tweak anything and they hurt you or make you even less effective, then all the eyeballs come looking at them,” he says. “I saw that a lot.” The consequence of cover-your-ass coaching was that players with the most talent received the least instruction.

During games, Bannister typically sits in the clubhouse, consulting Statcast to monitor pitch selection, spin, and speed changes that might indicate injuries. If a pitcher encounters command problems, Bannister checks KinaTrax for mechanical misalignments, and when other issues arise, pitchers (or pitching coach Dana LeVangie) walk through the tunnel to ask for advice. But much of the magic occurs before games, when Bannister turns the outfield or the bullpen into an interactive pitching lab, setting up cameras and tracking devices and inviting pitchers to ask each other questions, share information, and experiment in a more focused way than they can while playing catch casually. “I’ve found that kind of coffee-shop environment builds a lot of culture, because you get pitchers talking about their craft more openly,” he says, adding, “There’s all kinds of little miracles that happen with guys that pump their game up a little bit.”

It also helps that, Haren and the Rangers’ Brandon McCarthy aside, none of the players made bank by big-league standards, which makes them more willing to keep working. “I’m sure a lot of it is correlated to what your bank account looks like,” says former outfielder Sam Fuld, whose account was boosted by about $7 million over an eight-year MLB career that ended in 2015. Fuld joined the Phillies in 2018 as major-league player information coordinator, a nebulous label for a broad role.

Gone are the days when much of the minor-league system was outside the skipper’s purview; a modern manager is expected to be plugged into player development. “When I got called up [by the Cubs], [Manager] Lou Piniella had no idea who I was,” Fuld recalls. “He was like, ‘Can you play left field?’ [I thought], ‘Sure, but why don’t you know this?’”

LOL

In 2013 at the Texas Baseball Ranch, Dutch athletic trainer Frans Bosch delivered a guest lecture in which he referred to University of Georgia kinesiology professor Karl Newell’s theory of constraint training in motor learning. Bosch told the audience that altering one of three variables during practice improves the pace of progress. Bauer was listening closely. “It turns out the quickest way to acquire a new skill is to force yourself to do that skill with a constantly changing environment, implement, or activity,” Bauer says. “If you can vary one of those [elements] every single time, with the same goal, then your body acquires that skill a lot more quickly.”

A 1994 study conducted by California Polytechnic State University tested random batting practice versus block batting practice.2 The study divided thirty junior college baseball players into three groups: control, blocked practice, and random practice. The hitters faced three types of pitches—curveballs (CB), fastballs (FB), and changeups (CU)—in fifteen-pitch sets. The random group’s hitters faced the three pitch types in unpredictable fashion: FB, CU, CU, CB, FB, CB, and so on. The blocked group’s list of pitches came in segmented groupings of fifteen consecutive pitches of identical type: FB, FB, FB; CU, CU, CU, CB, CB, CB, and so on. In the testing phase, the researchers found that “the random group performed significantly better than the blocked group” in quality of contact under game conditions.

Mindset is a psychological concept that’s already earned its own TED Talk. As noted earlier, Stanford psychology professor Carol Dweck turned “mindset” into a business buzzword when she codified an attitudinal difference that could help explain the separation between high and low achievers. “Individuals who believe their talents can be developed (through hard work, good strategies, and input from others) have a growth mindset,” she wrote. “They tend to achieve more than those with a more fixed mindset (those who believe their talents are innate gifts).”1 The Astros value a growth mindset in their players, and more than anyone else, they also embody it as a franchise. They’re baseball’s best proof that even elite performers possess untapped talents.

The scout recalls one incident from his first year with the Astros that hammered that home. “I got laughed at, like literally laughed in my face, because I turned in a fifth-year senior catcher who could catch bullpens,” he says. “Maybe if somebody went down, there’s value in a guy who can catch, right? It doesn’t have to be a big leaguer, but there is organizational value. So I turned that guy in… and they just laughed at me. ‘This guy’s got a minus fifty stat score.’”

Even though NDAs bar analysts and coaches from taking team property with them, they can’t forget what they know. That presents a problem, because although the Astros have modernized player development by breaking down barriers between baseball worlds, they aren’t indivisible. The pursuit of a championship acted as a unifying force, but in the wake of the 2017 title, even some nonscout Astros sources grew disgruntled, believing that Luhnow was becoming too cost conscious and overly reliant on numbers—criticisms that external sources once lodged during the Astros’ no-holds-barred rebuild. Front-office members have clashed over a series of subjects, including how much information to share with scouts, how many scouts to employ, and whether to trade for reliever Roberto Osuna, whose 2018 acquisition in the midst of a domestic-violence suspension—followed by Luhnow’s convoluted attempt to square the swap with a supposed “zero-tolerance policy related to abuse of any kind”—caused a public backlash. According to multiple sources, most or all of the front office was strongly opposed to that trade, but Luhnow—who had earlier been talked out of drafting Oregon State pitcher and convicted child molester Luke Heimlich, who has trained at Driveline—rammed it through regardless, with Crane’s support. The same pursuit of inefficiencies that prompted the GM and owner to strip-mine the roster and revamp player development convinced them to cross a line that many of their own recruits consi...

According to those most familiar with the nature of spin—Driveline Baseball researchers, Bauer, and perhaps University of Illinois physics professor Alan Nathan, an MLB consultant—such a sizeable increase is unlikely to occur naturally with such consistent velocity. “It’s probably pretty hard to change that [fastball spin] ratio for an individual,” Nathan told FiveThirtyEight. “A fastball is pure power. There is no finesse.”

The only method that Bauer and Kyle Boddy identified of increasing rpm/mph rates on a fastball was applying a sticky substance to a pitcher’s hand or ball to improve the pitcher’s grip, thereby increasing spin. Boddy responded to a tweet Travis sent to publicize the story on Cole by accusing Cole of applying such a substance. “Fuck it, I’ll say it,” Boddy tweeted on April 11. “It’s pine tar and/or Firm Grip. Use them if you want a higher spin fastball or slider.” Bauer, in turn, tweeted that “pine tar is more of a competitive advantage in a given game than steroids.” It sounded hyperbolic, but he had data to support his claim, showing the league-wide difference in results on four-seamers bucketed by spin. During the 2018 season, batters hit .270 with a 7.5 percent whiff-per-pitch rate against fastballs with spin rates ranging from 2,000 to 2,299 rpm, .245 against fastballs between 2,300 and 2,599 rpm (9.8 whiff percent), and .226 against fastballs with a spin rate of 2,600 rpm or greater (11.9 whiff percent).

Pressly’s spin rate didn’t increase in Houston, although that doesn’t mean he wasn’t benefiting from a sticky substance. In August 2018, television cameras caught him spraying a substance on his left forearm in the visiting bullpen in Oakland. He then touched the forearm between nearly every pitch after he entered the game. It’s common to see pitchers touching their caps, gloves, forearms, and pants while they’re on the mound, but this was a more brazen display.

In the first inning of his April 30 start against the Rangers, Bauer threw nine fastballs. They were unlike any fastballs he’d thrown before or would throw after in 2018. The spin rate of those first-inning fastballs against Texas averaged 2,597 rpm (at 93.5 mph). During the rest of that start, the figure fell to a much more typical 2,302 rpm (93.2 mph). For one inning, Bauer had increased his fastball spin rate nearly 300 rpm. What happened? “No comment,” Bauer told reporters the next day, when people pointed out the rpm spike and asked if he’d applied a substance to the ball. Bauer went on to make additional comments to a swarm of reporters that gathered around him as the SpinGate controversy blossomed. “There is a problem in baseball right now that has to do with sticky substances and spin rates,” Bauer said. “We know how it affects spin rate and we know how spin rate affects outcomes and pitches and movement that have a big difference in a game, a season, and each individual player’s career.… The people who choose not to do it are at a competitive disadvantage.”

In the absence of an MLB investigation, Hardball Times writer Bill Petti analyzed publicly available Statcast spin-rate data from 2018. According to his previously unpublished research, the team with the biggest average intra-inning drop-off in four-seam fastball Bauer Units between the first and last four-seamer of an inning was—plot twist—the Indians, at 2.6 standard deviations above the mean. The Astros ranked 10th, although admittedly Petti’s method wouldn’t detect more regular application between pitches, and it’s impossible to isolate the impact of sweat on mph/rpm rates within an inning. (In 2017, the Indians and Astros ranked 2nd and 18th, respectively.) According to Petti’s numbers, Bauer ranked 169th out of 178 pitchers with at least 50 five-fastball innings in 2018, more evidence that he was pitching a clean (nonsticky) game. Cole ranked 27th, up significantly from previous seasons.

I preen, unreasonably proud of my pelvis.

There’s just one problem: my pelvis—the one part I thought I could count on—has betrayed me.

Although the details are different, in McKay’s mind the impulse to measure every aspect of player performance is similar in spirit to the way any evaluator would assess, say, a forty-yard dash. “They would never just watch the guy run and go, ‘That’s really fast’ or ‘They’re kind of slow,’” he says. “They would take a stopwatch. Well, we now have a stopwatch for all of these other parts of the game.”

Bauer plans to enter free agency after the 2020 season, and intends to market himself as a pitcher who can throw every four days and exceed 250 innings in a season. He wants to sign only one-year deals.

Inspired by Bauer’s willingness to experiment, Michael Baumann, a writer for the website The Ringer, took the opportunity to create some satire on Twitter. What could go wrong? “Trevor Bauer says that the doctors’ timeline for his return is based on outdated mainstream medicine and he’s begun a course of blood transfusions and colloidal silver to rid his body of CIA nanites. He anticipates missing two starts, three tops,” Baumann wrote. On MLB Network, an anchor reported and read aloud Baumann’s tweet as if it were actual news. Bauer was furious. The misinterpreted tweet made him appear ridiculous.

Drafted by the Moneyball A’s, he’s in his late thirties, younger than some active major leaguers. He reached Triple-A in the mid-2000s. Yet attitudes have evolved even over the course of his career. “The overwhelming paradigm that was pushed by the oldest generations of baseball was you need to be a tough, gunslinging, beer-swilling, slump-buster-finding asshole of a cowboy to be a good baseball player,” Baker says. “And what we’re realizing now [is] that that’s not necessarily a paradigm for anything… other than ruining a marriage and being unhappy.”

In 2018, emboldened by the new paradigm, the Cubs’ players adopted a practice that once would have been as unthinkable as technology tracking every pitch. “Starting in spring training, they were getting together as a position-players group, and they were talking about all of the times where they feel shitty on the baseball field,” Baker says. “From [Anthony] Rizzo to [Kris] Bryant to the lowest guy in the minor leagues, they were opening up and expressing to each other, showing that they’re actually real people that are vulnerable. That was a massive turning point for us because it gave people the freedom to not feel like they had to be perfect.”

The Cubs, who plan to conduct their own research with players in the instructional league, obtained data on Jha’s program that Baker says “shows a cognitive increase when people do it seven days a week and just a stabilization of cognitive function at something as small as three times a week, twelve minutes a day.” At the start of spring training, they present their players at all levels with a one-page summary of the scientific benefits of mindfulness practice, and they promote the regular use of free meditation apps. The resulting program is a mixture of hard science, Stoicism, and Eastern philosophy. “All the stuff that we do works great for the general population to bring them back to homeostasis,” Baker says. “But when you put those things onto the elite athlete, our vision is that it elevates them beyond what they are now.” The goal, Baker says, is to get players to reset and dismiss distractions before each pitch, allowing them to “play thought-free and allow all of the years of practice and training that is based on all of these scientific measures now to just express itself.” To do that, they have to “consciously and nonjudgmentally come back to this moment right now and go, ‘So, that happened. Now what am I going to do about it?’”

“Since the Cubs won the World Series [in 2016], they put a lot of money into nutrition at every level,” Myers says. “Each level has a nutritionist.… You have your protein smoothies, your weight-gaining smoothies, your hydration smoothies. You pretty much have everything you possibly need.” Myers is also a proponent of breathing exercises that he learned from the mental-skills staff. Whenever he’s under stress on or off the field, he breathes in for five seconds, holds it, and then breathes out for five seconds, which, he says, helps him “get myself locked into any situation.” He studies his TrackMan readings and praises the Cubs’ coaches, who he says, “always have something at your fingertips for you to take that next step in getting better.”

Even so, the Rockies were skeptical about the camera. “Is this gonna put more things in your head?” asked Rockies manager Bud Black and his staff. The self-effacing Ottavino had a reputation as an intelligent player but also as a “thinker,” which can be a dangerous label in a major-league clubhouse. “When a person who’s perceived as intelligent or a thinker struggles, they think you’re overthinking,” said Ottavino, describing an issue also plaguing Bauer. “That was part of what I was hearing [in 2017] is, ‘Oh, you’re just overthinking things.’”

Not long after Aaron’s comments, Adam Ottavino—who hasn’t thrown 100, but has thrown 99.8—told MLB.com’s Statcast Podcast, “I would strike Babe Ruth out every time.”

In the off-season, Alex Hassan notes, players have historically had little contact with their teams. “A lot of the off-season is like, ‘Hey, go get ’em, we’ll see you next year.’” That’s about to change.

Over the course of the regular season, though, both Kelly and Hembree had slowly lost their nasty sliders. Relievers who throw a lot of sliders, Bannister says, tend to release them with their hands slightly turned to the side, as if they’re throwing a football. That hand position imparts extra spin to the slider compared to holding the hand more square to home plate, which adds extra hop to the fastball. When the season started, Kelly and Hembree had their hands at an angle and threw spin-efficient sliders with less hop on their heaters, but they both began to suffer from the same affliction. “As the year went on, for whatever reason, their hand[s] [were] getting more and more square on their fastball[s], and they were getting more and more carry on their four-seamer[s], and we started to see them lose their sliders,” Bannister says. The wipeout pitches they’d been throwing in April had devolved into “baby cutters” that weren’t missing many bats. There was one happy by-product of this unintended alteration: pitchers who throw with their hands square to home also tend to have better curveballs. And so, Bannister says, “We actually saw Joe and Heath’s curveballs getting better while their sliders were getting worse.”

With the playoffs approaching and both pitchers unable to trust their sliders, Red Sox pitching coach Dana LeVangie, Bannister says, made a bold decision: “Let’s just completely eliminate the slider, and let’s go to [the] curveball.” Although both pitchers’ ideal sliders were better than their ideal curves, they couldn’t execute the sliders, and they could execute the curves. Kelly threw his last slider of the season on September 19. Hembree threw his on September 29. The chart shows how Kelly (solid lines) and Hembree (dotted lines) saw their slider whiff rates sink month by month through September. It also reveals how their usage of sliders gradually gave way to curves, culminating in a slider-less October.

The strategy worked wonders. Hembree allowed zero runs in his four playoff appearances, including a routine 11th inning in an epic World Series Game 3. The Red Sox reliever with the next-lowest ERA was Kelly, who led the bullpen with 11 1/3 innings pitched over nine games and allowed only one earned run, striking out 13 without issuing a single free pass—an extraordinary feat for a pitcher who’s normally not stingy with walks. Despite his pedestrian regular-season stats, he signed a three-year, $25-million deal with the Dodgers in December.

“Every once in a while [Barnes] goes, ‘What do you got for me?’” Bannister says. One of those times came on October 14, in the pitching lab in right field before ALCS Game 2 against Houston, with the Sox trailing the Astros 1–0 in the series. “I just said, ‘[Lance] McCullers and [Ryan] Pressly are going out there and, for lack of a better term, McCullers-ing us to death with breaking balls,’” Bannister recalls. He suggested to Barnes, “Why don’t you just go out there and just mirror them and do it right back?” That night, Barnes relieved David Price with two outs in the fifth inning, runners on first and second, and Boston up by one run. Facing Marwin González, he threw four consecutive curves to end the threat: called strike, swinging strike, foul, swinging strike three. The next inning, he threw ten curves in eleven pitches, going groundout, pop fly, groundout. He’d thrown 93 percent curves, easily exceeding his career high in an outing of more than two pitches. “That just said [to the Astros], ‘Hey, if you’re going to do that, we have guys that can do that too,’” Bannister says.