On Monday, MLB will begin a dramatic, strict crackdown on foreign substances. The sudden removal of sticky stuff from pitchers’ hands across the game, after most used it without worry for years — if not their entire pro careers — will change the game on the field and in the box score.
The question is: How?
In a sense, the 2021 season will be divided into two distinct eras. With sticky stuff and without. Pre- and post-crackdown. The numbers thus far will come in a different environment and with different context than those that come after.
Fans, bettors and oddsmakers will be frantically trying to get a grasp on the new state of play, which should theoretically boost offense, but resist the urge to rush to conclusions. If we’ve learned anything in recent seasons, it’s that changes to the game often have more ripple effects than anticipated.
In the immediate short-term, BetMGM trader Darren Darby says the increased enforcement won’t change day-to-day handicapping — citing the uncertainty around which pitchers would even be affected, and bettors’ established proclivity for betting overs.
As it plays out over the second half of the season, though, we might be able to observe substantive, actionable changes. Here are the key things to watch.
Whose spin rates will change, and how much?
A lot of pitchers, probably the vast majority, were using some form of sticky stuff to help maintain a consistent grip and boost their stuff. There’s no need to retroactively vilify anyone for doing a thing that was practically allowed and available to all, but certainly some pitchers’ profiles will change more than others without the tacky substances.
Since the initial word of the coming crackdown came on June 3, amateur detectives have been ogling Statcast data for evidence that individual pitchers have stopped using sticky stuff. Spin rate — which measures how fast the ball is spinning and helps quantify a major element of how a pitch moves on its way to the plate — is indeed the place where we would expect to find the impact of the crackdown, but it’s important to understand the context before sending up flares panicking about Gerrit Cole or some other ace.
First, spin rate can fluctuate for all sorts of reasons. Most changes in a small sample mean nothing at all. A pitcher’s fastball being down 50 rpms from his season average is not worth sounding the alarm over. Real meaningful change is more in the realm of hundreds of rpms over a full outing. And even then, it’s more useful to control for velocity — faster pitches naturally have more spin — and look at the ratio of spin to velocity known as Bauer Units to detect real shifts.
As we get more data on this, it’s also worth remembering that boosting spin matters far more for certain pitch types and thus certain pitchers who rely upon them. The success of four-seam fastballs, the type that appear to rise or hold their line and are often thrown up in the zone, is particularly correlated to spin rate. More spin means more defiance of gravity, which means more of that “rising” action that befuddles hitters and eludes bats. Sliders and curveballs are similarly turbocharged by high spin: Faster spin means a tighter, more dramatic break.
Sinkers (or two-seam fastballs), changeups and splitters are not typically aided by higher spin, and often actually function better with lower spin. So pitchers who build their repertoire around those offerings — think Kyle Hendricks or Dallas Keuchel — may not experience much meaningful change if they even used sticky stuff in the first place. Meanwhile, other prominent pitchers, including White Sox stars Lance Lynn and Carlos Rodon and Brewers closer Josh Hader, get more than half of their crucial swinging strikes from their four-seam fastballs.
Will pitchers change their approach?
The next question is whether pitchers who find their stuff diminished decide to change how they deploy it. MLB’s ideal end result probably involves pitchers being incentivized to at least occasionally pitch to contact.
Since Statcast allowed for more granular analysis, including spin rate, the optimization of pitching has pretty much been an ever more fervent effort to miss bats. That mostly translates to throwing more fastballs higher in the strike zone and more sharp breaking balls that look like those high fastballs riiiiight up until they dive for the dirt.
The worst reason pitchers might change is a fear of injury. MLB did plenty of research on what was happening with foreign substances, but apparently did not spend much time thinking about the consequences of forcing everyone to stop suddenly midseason. Rays ace Tyler Glasnow — one of the most successful practitioners of that optimized style of pitching — injured his elbow and blamed the crackdown for forcing him to grip the ball harder. If pitcher attrition proves abnormally high as this enforcement kicks up, it would be a black eye for the league and possibly force MLB to change course.
But in terms of pure results, it’s hard to say at this point whether a real shift is likely.
Prior to June 3, 26.2 percent of four-seam fastballs had been thrown high in the zone or in the immediate area outside it. Hitters whiffed at 37.5 percent of the time they swung.
Since June 3, a virtually identical 27.2 percent of four-seamers have been up, and hitters have whiffed on 37.1 percent of their swings. If reduced spin leads to substantially more hitter success once the enforcement is fully in effect, it could push back on the orthodoxy of high heat that has taken hold in recent seasons.
There’s been a bit more budge on the breaking ball front. Batters league-wide were hitting .203 and slugging .351 on sliders before June 3, and have hit .208 with a .370 slugging percentage since then. On curveballs, average has edged up from .204 to .220 and slugging from .326 to .347.
And overall, there are hints at an effect. The contact rate (how often batters make contact when they swing) prior to June 3 was an all-time low 75.2 percent, and in the much smaller sample. Since June 3, it’s up to 76.2 percent — back to 2019 levels. That was still historically low at the time, but hey, leveling off counts as progress.
However, it’s unlikely even those relatively minor improvements are all related to sticky stuff. So envisioning wholesale strategy changes based on the crackdown still feels a bit far-fetched.
Will scoring be up across the board?
Almost certainly … just not necessarily for the reasons you’re thinking.
Even if no one had ever uttered the “sticky stuff” phrase, scoring would be on the rise right now. Summer means more heat, thinner air and an overall more conducive atmosphere for home runs, which drive much of the scoring in MLB — and it’s possible that’s even more true with the 2021 version of the baseball.
Another complicating factor might be how sticky stuff was affecting the baseballs once they were hit. At Baseball Prospectus, Rob Arthur has shown a significant, curious change in how the ball is flying since June 3, theorizing that removing the residue of tacky substances might be making more balls more aerodynamic and allowing them to fly further. Count that as another boon for hitters, just not for the reasons we expected.
Prior to June 3, the league was running a 4.03 ERA, allowing a .236/.312/.395 slash line. Since June 3, pitchers collectively have a 4.37 ERA and hitters are slashing .246/.316/.416.
To truly watch the macro-effects of the crackdown, though, you’ll want to monitor the aforementioned contact rate and strikeout rate. Hitters are striking out in 23.1 percent of plate appearances since June 3, where that number was at 24.2 percent prior to word of the impending enforcement.
The overarching changes, in the end, are unlikely to be as dramatic as MLB’s crackdown and the ensuing discourse, but there are reasons to believe offense will be up and certain pitchers may be forced to adjust — if only until they find a new way to stay one step ahead.
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