Eight Lingering Questions About MLB's Crackdown on Sticky Stuff
Diving into the data, ripple effects, and potential issues surrounding baseball's plans to begin enforcing its ban on foreign substances for pitchers
By Ben Lindbergh Jun 16, 2021, 6:30am EDT
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Last week, a book came out about Major League Baseball's recent sign-stealing scandal. Another is due out in August. But that type of cheating is already old news. MLB has a hotter cheating scandal on its hands (and its caps, gloves, and belts): pitchers' use of foreign substances to enhance their grips, spin, and movement. If the sign-stealing scandal was the new steroids scandal, then foreign substances are the new sign stealing. Of course, neither sign stealing nor pitchers' use of foreign substances is actually new; both methods of gaining an illicit edge date back to the 19th century. But just as it did in the aftermath of the late-2019 revelations about the "banging scheme" employed by the 2017 Astros, MLB has belatedly decided to do something about a preexisting practice, prompted by press and public scrutiny, technological innovations, and larger changes in the game.
Almost two weeks ago, word leaked out of an MLB owners meeting that the league was about to get serious about preventing pitchers' use of foreign substances, which has been banned for more than a century by what are now rules 3.01 (about damaging or discoloring the ball) and 6.02(c-d) (about otherwise altering or applying substances to the ball). That news followed a yearslong lead-up to sticky stuff becoming a crisis, highlighted by several pivotal developments: then-Cleveland pitcher Trevor Bauer implying in May 2018 that the Astros were using foreign substances to increase their spin rates, after which Bauer publicized evidence of such substances' spin-augmenting effects and apparently applied those substances himself during a one-inning, in-game demo; Bauer seemingly embracing foreign-substance use full time in September 2019, and enjoying a corresponding spike in spin rates, which was followed by a Cy Young season and a record contract; MLB sending a pre-pandemic memo to teams in February 2020 about enforcing rule 6.02; the Angels firing their visiting clubhouse manager, Brian Harkins, in March 2020 for allegedly providing pitchers with foreign substances; and MLB sending another memo in March 2021 about enforcing rule 6.02 for real.
Although no major league pitchers have been punished yet, the drumbeat about a coming crackdown has been building all season, amplified by sporadic developments and reports: news about balls thrown by Bauer and others being collected for testing; players expressing frustration about MLB merely monitoring sticky-stuff usage without taking direct action; umpire Joe West confiscating the cap of Cardinals pitcher Giovanny Gallegos, prompting Cardinals manager Mike Shildt to call sticky stuff "baseball's dirty little secret"; and multiple minor league pitchers being suspended for foreign-substance use. On June 5, following earlier rumors, ESPN's Buster Olney published a report about MLB's plans, which he supplemented a week later. On Monday night, ESPN's Jeff Passan previewed the contents of MLB's memo, which was distributed to teams on Tuesday and also obtained by The Ringer.
Per MLB's team memo and press release for media members, enforcement will begin in earnest next Monday, June 21, and will involve umpire inspections of every pitcher in every game, with each starting pitcher undergoing multiple mandatory checks. Catchers will also be subject to "routine checks," and any players found to be breaking the newly binding rules will be ejected from games and subject to 10-day suspensions with pay. The ban will encompass not only ultra-sticky stuff such as Spider Tack, but also any other substance that violates the letter of the law, including less exotic (and less-spin-enhancing) staples such as pine tar and mixtures of rosin and sunscreen.
Numerous reports (including my own from last July) suggest that the vast majority of major league pitchers have been using some substance that's about to be targeted, which means that most pitchers may have to learn on the fly how to pitch without a tool they've been accustomed to using for years—in some cases, perhaps, the entirety of their professional careers. As soon as next week, in theory, baseballs thrown in major league games could be universally substance free for the first time … well, ever. And whereas the rampant employment of illegal sign stealing was seemingly limited to certain teams, and the effectiveness of even Astros-style sign stealing is somewhat in dispute, sticky substances certainly improve pitcher performance, on the whole—and thus potentially exert some influence over almost every pitch.
What Will Happen After MLB's Sticky Stuff Crackdown?
That's why this story could be a big deal. While the effects may turn out to be more muted than hoped (or feared), there's some possibility that they'll have a significant impact on the performance of individual players—and, by extension, teams—while altering the leaguewide offensive environment. Those are just the intended consequences of the crackdown, which could also produce secondary effects ranging from adjustments in player approach to safety concerns to heightened tensions between the players and the league. All in all, then, this sweeping overhaul of the league's attitude toward sticky stuff constitutes a fairly drastic change to make at midseason, even though the writing has been on the wall since last spring and the rules on the books aren't changing. (MLB's previous adventures in clarifying and abruptly enforcing preexisting rules, such as the short-lived "Year of the Balk" experiment in 1988, tended to take effect at the start of the season, not more than 40 percent of the way through the schedule.)
The sticky-stuff discourse has exploded over the past two weeks, as reports of approaching prevention and discipline have multiplied and players have weighed in (or awkwardly avoided weighing in). Josh Donaldson publicly called for the crackdown and alluded to the sticky-stuff rumors that have stuck to Gerrit Cole, who subsequently struggled to answer a question about whether he'd ever used Spider Tack (but didn't struggle to retire Donaldson). The Angels' ex-visiting clubhouse manager, whose lawsuit against the team and the league was dismissed, started speaking out and sharing receipts. (Adam Wainwright, one of the pitchers Harkins named, copped to using foreign substances, though in Andy Pettitte–esque fashion, he claimed to have tried it only briefly.) Pete Alonso pivoted from answering a question about sticky stuff to advancing a fairly far-fetched theory about MLB manipulating the baseball's behavior to suppress spending on free agents. And intense scrutiny surrounded suspicious spin-rate dips by Bauer and other pitchers, as Twitter detectives scoured Baseball Savant for signs of guilt or innocence. Those public private eyes are only emulating MLB's investigators, who have already documented pitchers' "prevalent" use via video, Statcast, lab testing, and on-site observation and provided those incriminating dossiers to teams.
Even though the no-foolin' ban has yet to take effect and the details weren't announced until Tuesday, it's apparent from reporting, public admissions, and data alike that some pitchers have already begun to surrender their sticky stuff or switch to less advantageous substances as a way of weaning themselves off the hard stuff. On an individual level, spin-rate results can fluctuate by dozens (or more) revolutions per minute from game to game based on changes in velocity, mechanics, and weather, as well as measurement errors, park effects, and other factors. But leaguewide spin rates are stable enough, and enough four-seam fastballs are thrown each day, that the daily league averages for four-seam spin rate and velocity-adjusted four-seam spin rate (RPM/MPH, also known as "Bauer units") can give us some sense of overall trends. In this case, the recent trend is sharply downward.
The six lowest-spin days of this season, as measured by both raw RPM and Bauer units, have come since June 8. If you think that's a complete coincidence, I have some soon-to-be-outlawed sticky stuff to sell you. In the seven days beginning on June 8, the average four-seam spin rate was 2267 RPM, down 51 points from 2318 this season prior to that point. There was no corresponding decrease in fastball speed, which actually rose by a tenth of a mile per hour. Over the same span, curveball spin rates fell 72 points, slider spin rates fell 57 points, and changeup spin rates fell 43 points. While those drops aren't precipitous, they're sufficient to erase the last few years of spin-rate rises, bringing the average spin rates over the past week roughly in line with 2018 levels. There's no recent precedent for a leaguewide month-to-month four-seam spin-rate change this dramatic—and if the results so far this month hold up or accelerate in the next two weeks, the graph below will look a lot more extreme by the end of June.
Again, these declines occurred before pitchers had any pressing reason to give up their advantage. That might mean that every pitcher who was using sticky stuff renounced it as soon as the slightest pressure was applied. Alternatively, it might mean that even bigger drops lie ahead. We can't perfectly forecast every ramification of the sport's new stance on surveillance before the impending policies go into effect, but we can still speculate and identify potential pros and cons based on what we know now. Let's run through eight questions about the sticky-stuff scandal/enforcement saga, some of which we can answer immediately but most of which we'll need weeks, months, or even years to assess.
Why is this happening now?
Why is June 21, 2021, the appointed day, as opposed to 20 years ago, two and a half months ago, or next Opening Day? MLB (or team owners and league presidents in the days before the commissioner's office consolidated control of the sport) could have made more of a point—or any point at all—of stopping sticky-stuff usage decades ago. But aside from sporadic searches of obvious offenders, the powers that be were, until very recently, largely content to preserve the sticky status quo, even though it's long been clear that this type of rule-breaking was rampant. Ball-doctoring/defacing has been celebrated or dismissed as an amusing or quaint quirk more often than it's led to lasting condemnation.
Historically speaking, the league has tended to lurch from crisis to crisis, ignoring festering problems—if not creating or tacitly or actively condoning them—until a catastrophe of some kind occurs. Sometimes it's a traumatic injury that exposes unsafe conditions. Sometimes it's a cheating scheme or off-the-field scandal that gives the game a bad name. Most of these situations are foreseeable, but the league tends to be complacent until they come to a head (or come to light), at which point it tries to minimize the damage, downplay its own culpability, and change the subject as quickly as possible. This reactive, cover-your-ass approach isn't unlike the life strategies many other corporations and people adopt, but MLB's brand of head in the sand leads to a lot of situations where the league is ostensibly shocked to discover something untoward that was actually lurking in plain sight.
For a variety of reasons, the steroids, sign-stealing, and sticky-stuff scandals eventually became untenable for MLB to ignore. One element the Astros sign-stealing scandal and the present kerfuffle have in common is an active pitcher—Mike Fiers or Bauer—breaking clubhouse code to call out specific players or teams. And although many cheating allegations are based on hearsay or testimony that surfaces long after the fact, the latest controversies centered on persuasive evidence that's accessible to the public, in the form of audible bangs on broadcasts or glaring spin-rate spikes. The fallout from the Astros scandal seemingly made the league look around for ticking time bombs, and it didn't have to look far to find foreign substances.
So yes, the league was lax in waiting this long to take action, especially after Bauer helped push sticky stuff into the spotlight. But it's also true that the problem has become much more pressing in recent years. The advent and widespread adoption of TrackMan, Rapsodo, and Statcast technology in the middle of last decade enabled players and teams to measure spin and quantify its effects. That process revealed that there were real advantages to using sticky stuff—and bigger edges to be gained by applying more elaborate chemical pastes. Just as the data-driven reappraisal of catcher framing prompted teams to teach or acquire skilled receivers and catchers to refine their receiving technique, the appraisal of spin and reappraisal of sticky stuff helped fuel a foreign-substance arms race. This competition occurred in an era when the sport was already in the throes of a rising-strikeout-rate streak that has entered its 16th season. The low-contact, all-or-nothing nature of the modern game has intensified the focus on any factors that could be contributing to Ks.
(The largely unenforced ban on foreign substances has been on the books for so long because of a similar progression from minor nuisance to acute crisis. Pitchers started throwing spitballs at least as early as 1868, but for the first few decades, they only wet the tips of their fingers before touching the ball. Around the turn of the century, though, some particularly cunning and unhygienic players discovered that by really loading up with gobs of spit, they could make the ball spin more. As the weaponized pitch spread, scoring fell, hitters complained, and the media made a stink: In 1917, Grantland Rice pronounced that the number one way to "give the attack a chance" and restore a "more attractive game" was to "eliminate the spitball, or the application of any outside matter to the cover." Finally, in 1920, the Joint Rules Committee did just that, although it allowed some existing spitballers to keep throwing the pitch, often to great effect. History repeats itself, right down to the stewards of baseball taking their sweet time.)
It's still unusual that the league would take this step without waiting for the season to reset. To be fair, the pandemic may have put a crimp in the league's plans to intervene a little sooner—sometime last season, say, or at the start of this one. (In addition to the logistical challenges of staging a season in pandemic conditions that might have taken precedence over sticky stuff, frequent physical inspections probably wouldn't have meshed well with pre-vaccine pandemic protocols.) There's nothing preventing the league from waiting for 2022 to take the next steps, but the discontent among hitters (and some pitchers) about the lack of a clean, level playing field seems to have grown. Beyond that, the fretting about this season's 1968-esque batting averages and possible record number of no-hitters has put pressure on the league to act. Granted, the league likely exacerbated the offensive outage by intentionally deadening the ball. It's possible that MLB is attempting to stage a diversion to obscure its own role in creating the current conditions. Alternatively, the league may be trying to scapegoat the players before the final stages of the public battle over the next CBA.
Dave Roberts on the midseason MLB crackdown on sticky stuff: "If it wasn't reactive, it wouldn't happen in the middle of the season."
— Fabian Ardaya (@FabianArdaya) June 15, 2021
From a purely analytical perspective, though, the timing may pay off. Rooting out sticky stuff almost halfway through a season, as opposed to at the start of one when other conditions could have changed, makes it easier to isolate the effects (aside from the fact that warmer weather will skew before-and-after offensive comparisons). As the league and the players weigh various proposed rules changes and negotiate about what baseball will look like under the next CBA, there's value in knowing now whether removing foreign substances is a solution to any of the sport's aesthetic ills.
How will the blame be distributed?
There's plenty to go around. As covered above, MLB bears responsibility for not stepping in sooner, and also, perhaps, for the year-to-year and batch-to-batch variability in the ball, which has led to frequent complaints of inconsistent and slick surfaces and seemingly driven more pitchers to search for grip enhancers. True to form, the league isn't eager to fall on its sword.
In its Tuesday press release, the closest MLB came to saying "Our bad" was Manfred's acknowledgement that "we have a responsibility to our fans and the generational talent competing on the field to eliminate these substances and improve the game." If the substances have been prevalent to this point, it follows that MLB has thus far failed to uphold its responsibility. Manfred also stated, "I understand there's a history of foreign substances being used on the ball," an indirect admission that he and his predecessors let the use of sticky stuff slide for the past century or so. He just didn't directly and explicitly say so (or say sorry).
Teams bear blame too, both directly (for providing players with high-octane sticky substances and encouraging them to use them) and indirectly (for paying richly for free agents whose spin rates had climbed, thereby incentivizing others to take the same illegal leaps). And players' hands are far from clean, both literally and figuratively. Many pitchers flouted the rules for years and knowingly went well beyond what was needed just to get a grip.
For what it's worth, Manfred also said in the release that "this is not about any individual player or club, or placing blame, it is about a collective shift that has changed the game and needs to be addressed." But the ease of singling out well-known individuals compared to "collective shifts" and the understandable temptation to cite spin rates as smoking guns will likely lead to more fingers being pointed at players than at behind-the-scenes suits in front offices or at MLB.
How effective will enforcement be?
MLB hasn't suspended a player for foreign-substance use in more than six years. The umpires have basically been like state troopers who are still supposed to catch speeders, but who haven't camped out behind a billboard or turned on a siren since the Obama administration. In theory, umps have always been empowered to police foreign-substance use. In practice, though, the league hasn't instructed them to prioritize eradicating goop or had their backs in a forceful way when they've acted on something they saw and suffered the inevitable blowback. Those days are done. Although the punishments in this instance aren't so severe, the certainty of punishment can be a better deterrent. By building in inspections and possible penalties for catchers and other position players, MLB has made some of the obvious end arounds more difficult, but it remains to be seen just how thoroughly the umps will search and how clever the players can be about concealing substances. Even if the umps are on the ball (so to speak) early on, it wouldn't be surprising to see their vigilance slip as the season wears on, especially if they find few offenders initially.
Another potential problem is the banning of a basic, time-honored sticky substance—a blend of rosin and sunscreen. MLB is imposing an inflammatory blanket ban on virtually all substances, both because umps can't break out their chemistry sets on the field to distinguish between types of sticky stuff and because, according to MLB SVP of on-field operations Michael Hill, "the more traditional substances can be used for competitive advantage just like the more modern substances." Yet rosin is still legal on its own—there's a bag behind the mound—as is sunscreen, which is crucial in protecting players from skin cancer, an institutional hazard in a sport typically played outdoors (as MLB and the Players Association have acknowledged by partnering to raise awareness of the risks). Telling pitchers that they can keep the two substances separate but that they can't "intentionally" mix them together sounds as feasible as warning two teenagers with a mutual crush to keep the bedroom door open and their feet on the floor. MLB's press release says that pitchers have been told not to use sunscreen after sunset or when playing in parks with closed roofs, but outdoors during daytime, those dirty, sticky substances may meet up for some hot, illicit action.
Three other questions about potential enforcement scenarios: Will any club personnel be busted for supplying sticky stuff? Will anyone try to sneak an extra-sticky rosin bag past the umps? And will any guilty players refuse to be inspected and accept an automatic ejection and suspension to save themselves the indignity of being caught sticky-handed?
How much would eradicating foreign substances affect leaguewide performance?
Trying to answer this question is a little like trying to solve the Drake equation when most of the individual variables are still unknowns. In this case, we have estimates of the percentage of pitchers who are using certain sticky substances. We have estimates of how much those respective substances may enhance spin rate. We have estimates of how much spin enhances performance. But all of those estimates are imprecise, and putting them together only compounds the imprecision.
This much seems certain: Just as steroids weren't solely responsible for the offense-first conditions that prevailed during the PED era, foreign substances are merely one of many factors determining today's reduced and static offensive output, including increased velocity, optimized pitch selection, a bigger called strike zone (enlarged further by framing), and improved positioning. Decreased spin probably isn't a panacea. Baseball analyst Joe Sheehan, for one, speculates that the use of foreign substances would reduce leaguewide wOBA by only 1 to 2 points. That's a lot in the sense that the difference would stem simply from opting to enforce a rule that already exists. But it's also a little in that 1 to 2 points would be all but imperceptible on its own. (Leaguewide wOBA is down 10 points so far this season, relative to the full-season marks from 2019 and 2020.)
An unsticky sport is uncharted territory, so it's impossible to say with any certainty whether that guess (and other conservative estimates) are low. But it would be tough to square such a slight impact with what we know about how higher spin enhances performance (all else being equal), as well as how widespread the use of these substances is among players and teams. It's plausible that there could be sizable boosts to contact and scoring.
If we compare offense through May of this season with the corresponding rates in June (entering Tuesday), we might conclude that the batter boom times have already arrived.
MLB Monthly Offensive Splits, 2021
April-May .236 .312 .394 .705 .308 .288 24.2
June .246 .317 .417 .734 .319 .295 23.4
But those upticks don't seem so significant if we compare them to the cumulative April-May and June splits in the previous four full seasons.
MLB Monthly Offensive Splits, 2016-19
Offense always goes up as the weather gets warmer, so whatever happens during the rest of this season requires context. Of course, the leaguewide sticky stuff decline didn't get going until the second week of June, and the warmer half of the month is still ahead. For what it's worth, though, offense was slightly more elevated in the first week of this June (with higher spin rates) than it was in the second week of this June (with lower spin rates). And the four-seamer whiffs-per-swing rate was only slightly lower from June 8 through June 14 than it had been from opening day through June 7. Just as it's important to adjust for pitch speed when studying spin, it's important to adjust for weather when studying offense—and also to beware of small samples.
How much would eradicating foreign substances affect individual performance?
This one isn't any easier. It's tough to label any pitcher as purely a product of foreign-substance use. Cole was an All-Star before he departed Pittsburgh, and his subsequent success (and increases in spin rate) coincided with changes in training, pitch selection, and location. Bauer's best big league campaign, by Baseball Prospectus's deserved run average, was 2018, the year before his late-season spin-rate spike. Bauer's two starts in June have been shaky and walk-prone, but he still struck out 15 batters in 12 1/3 innings, so it's not as though he's suddenly lost the ability to miss bats after his Flowers for Algernon­–style spin-rate odyssey.
It seems almost self-evident that pitchers whose arsenals are more dependent on spin—whether because they're all stuff and no finesse or because they thrive on offerings (such as high fastballs) that play up with more RPM—would stand to suffer more from being deprived of sticky concoctions. But it also seems unlikely that a lot of great pitchers are about to turn into pumpkins compared to their peers, especially because whatever declines could be coming may leave few pitchers unscathed—a falling tide that lowers all boats. Entering Tuesday, 11 mostly low-profile pitchers (including Bauer, but not Cole) had lost more than 200 RPM and more than 2 Bauer units, on average, on their four-seam fastballs from May to June. Given some of the samples involved, though, it's a bit premature to brand most of them with the scarlet C.
Will hit by pitches become more common?
When Nationals pitcher Austin Voth was hit in the face while batting last week, his manager Dave Martinez insinuated that banning foreign substances would cause more such scares, saying, "I hate to bring it up, but you'll see more of that if we keep messing around with the stuff about the balls."
The last thing MLB needs is more batters getting beaned—or, for that matter, players getting plunked on any appendage. As MLB's press release points out, the rate of hit by pitches is at an all-time high in the modern era (as is the rate of wild pitches). Although the average speed and height of pitches that result in plunkings are both lower than they have been at any point in the pitch-tracking era—thanks to increased usage of breaking balls, which tend to be buried and thrown with less control—it's still scary to see hitters placed in harm's way in an era when the speediest pitches fly faster than ever. One of the most common justifications for foreign-substance usage (by both pitchers and hitters) is that it makes pitchers less likely to hit batters. It's evident that sticky stuff hasn't prevented pitchers from plunking batters, but it's still possible that hit by pitches would be even more frequent without sticky stuff.
Not so, insists MLB. The league's memo to teams asserted that sticky stuff is "predominantly utilized by pitchers not to aid grip but to increase the spin rate of the baseball and gain a competitive advantage." It also claimed, counterintuitively but not illogically, that sticky stuff decreases control because it "enables a style of pitching in which pitchers sacrifice control in favor of spin and velocity." (Perhaps we're also seeing the Peltzman Effect in action: If pitchers feel like their sticky stuff gives them greater control, they may be more likely to try to buzz batters.) MLB concluded, based on research that included "numerous conversations with accomplished current and former pitchers," that rosin alone is sufficient "to address any serious concerns about grip and control." Some pitchers have publicly echoed that sentiment, though many others would no doubt dispute it.
It would help clear things up if we knew exactly why batters are getting bruised more often. Possible answers abound: More pitcher's counts and more breaking balls mean more pitches outside the strike zone; faster pitches allow less reaction time; velocity is king and command is an afterthought. All of those hypotheses sound reasonable, including the command explanation. But some recent research suggests that hitters are driving the spike, and that pitchers aren't uncorking high-risk, far-inside pitches more often than before, which COMMAND+ stats supplied by Stats Perform seem to corroborate.
Batter positioning data provided by KinaTrax doesn't show any evidence that hitters have moved closer to the plate over the past few years, though they may have moved back a bit in the box, possibly to give themselves more time to react to faster pitches. Maybe they're wearing more protective equipment. Maybe they've gotten more willing to take one for the team. Or maybe they're befuddled by fast, high-spin, well-tunneled pitches that move more than ever, which prevents them from sidestepping pitches in spots where they once would have been easier to avoid. High-spin pitches fool batters by behaving like optical illusions. Maybe batters will be safer if they're better at predicting where pitches will end up.
What could some of the unintended consequences or secondary effects be?
The specter of one potentially disastrous side effect has already surfaced. This week, Rays ace Tyler Glasnow was diagnosed with a partially torn UCL and a flexor tendon strain, which at best could cost him most of the rest of the season and at worst would lead to Tommy John surgery and an even more extended absence. On Tuesday, Glasnow spoke passionately and persuasively about his belief that going cold turkey on his preferred sunscreen-and-rosin mix in the middle of the season directly contributed to the injury.
Tyler Glasnow sounds off on MLB's foreign substance crackdown and how it may have led to injury pic.twitter.com/47rcTnpk0l
— B/R Walk-Off (@BRWalkoff) June 15, 2021
Glasnow is an extremely hard thrower, and the track record for flamethrower health is riddled with arm injuries. (Glasnow has had wrist and forearm ailments in the past.) And sticky stuff certainly wasn't keeping pitchers intact: By late May, the number of Tommy John surgeries performed on MLB players had exceeded the total for all of 2019, and pitcher injuries were up relative to 2018 and 2019 before anyone started giving up sticky stuff. That said, taking sticky stuff away could still impose more pain.
Even if rosin is sufficient for throwing a ball without totally losing control, if a pitcher consciously or subconsciously tries to generate the same spin he was getting before, without the substance that enabled him to do that—and without any offseason or spring training–type setting in which to experiment—it's plausible that he could grip the ball harder, and that that could cause harm. At the very least, Glasnow's injury creates a perception problem. Maybe pitchers will hurt themselves more frequently. Maybe they won't, but the ones who do get hurt will blame the lack of sticky stuff. The first outcome would be bad, and the second would still look bad.
Other potential repercussions could be more of a mixed bag. Will pitchers nibble because they're afraid to try to blow the ball by hitters, producing even longer plate appearances and more offense in the form of walks? Will less sticky stuff slathered on the leather reduce drag and make batted balls carry farther? Will inspections slow down games despite MLB's best efforts to conduct them between innings or after pitching changes? Will certain teams be outed as egregious sticky-stuff felons by bigger-than-normal nosedives in spin rate, and would those differences decide pennant races? Will the union be divided by pitcher-batter bitterness or more motivated to stand up to heavy-handed MLB? Will sinkers and fastballs thrown low in the zone come back into vogue? Will we miss GIFs of whiffle ball–like offerings that move more than any "clean" pitch could?
What's MLB's long-term plan?
Maybe next week's implementation will work perfectly: Spin rates will sink, taking whiff and strikeout rates with them, and there won't be more beanballs or serious arm injuries than there were before. Fairness and peace will prevail, and baseball's problems with cheating and whiffs will go away.
Yeah, I doubt it too. Odds are that pitchers will continue to complain, perhaps partly justifiably, about being stripped of almost all sticky stuff in medias res (or maybe medias rosin). In the short term, MLB may back off and allow pitchers to add pine-tar rags to their rosin bags. In the long run, though, the solution may be another sort of sticky substance: a legalized goop that aids grip without sending spin rates soaring, or a KBO/NPB-style ball with a tacky cover that picky MLB pitchers would welcome.
For now, we'll wait a little longer for the official start of an experiment that somehow seems both premature and overdue, ill-considered and sensible. It might break baseball. It might save baseball. It might be barely noticeable. One way or another, we'll finally learn whether the cheaters were prospering, and whether the league that left them alone might have prospered by stopping them sooner.
Thanks to Lucas Apostoleris of Baseball Prospectus, Scott Coleman of KinaTrax, and Lucas Haupt of Stats Perform for research assistance.