Sun lotion and curveballs: Why MLB is gripped by dubious ‘foreign substances’

It’s a good time to be a pitcher in Major League Baseball: they are enjoying their most dominant season since 1968, which baseball historians refer to as “The Year of the Pitcher”. And it’s all the more welcome for the pitchers as they’ve spent the last few years being brutalized by the game’s sluggers. It may not last though. Last week MLB announced it will crack down on pitchers using “foreign substances”, forcing a reckoning with one of the league’s primary “don’t-ask-don’t-tell” rules.

What are the pitchers accused of?

Pitchers have tried to scuff balls since the game’s beginnings, and the league has long tried to prevent them from doing so. Rule 6.02(c) of the Major League Baseball regulations is a lengthy law against pitchers using foreign substances to doctor baseballs. The ethical debates on the subject go as far back as the 1890s, but it wasn’t until 1920 when leagues began legislating pitches like the spitball out of the game.

Why do pitchers do this?

A baseball is a sphere of cork covered in cowhide and stitched with yarn and the leather is slippery to the touch. Historically, pitchers used foreign substances like spit, sandpaper and vaseline to make baseballs move unnaturally. When a pitcher throws a traditional four-seam fastball, the ball leaves his fingers with a straight, rolling topspin akin to a bowling ball; a curveball usually leaves the pitcher’s hand at a lower arm angle and features a harder top spin that causes the ball to break downward with little to no sideways movement. Every pitch spins and every pitcher wants to control how much spin they can apply to the ball.

Pitchers used to apply foreign substances to decrease the level of friction, meaning a “spitter” could produce an unnatural side spin and could squirt off of the hand to deceive hitters. The most famous ball doctor was hall of famer Gaylord Perry, who famously said he “tried everything on the old apple, but salt and pepper and chocolate sauce topping.”

That form of doctoring the ball is passé. Now, pitchers use a series of gripping agents to increase the amount of friction between their fingers and the ball. By tightening their grip on the ball, they have stronger control of the ball when it leaves their hands.

So this isn’t a new problem?

No. Fans of the movie The Naked Gun may remember Frank Drebin’s inspection of a pitcher during his undercover mission as an umpire while Major League explained what may motivate a pitcher to apply nasal mucus to the ball. Longtime player and manager Gene Mauch once said that Perry should have “a tube of KY Jelly attached to his plaque” in the hall of fame.

Why are we talking about it now?

When asked recently if he has ever used a substance called Spider Tack, New York Yankees pitcher Gerrit Cole paused for about five seconds before stammering through a cringeworthy answer about “customs” and “practices” among pitchers. Cole is the highest-paid pitcher in baseball and a player who doesn’t need foreign substances to be one of the best players in the game. So why did he all but admit that he has used them?

Four days before Cole’s press conference, Minnesota Twins third baseman Josh Donaldson accused Cole of doctoring balls, asking whether it was a coincidence that Cole’s spin rate decreased after four minor league pitchers were suspended for using foreign substances. Donaldson is a former American League MVP and known as one of the game’s most astute hitters. He eventually clarified that he wasn’t trying to single out Cole, but that the use of these substances has gotten out of control.

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Hold on, what is “spin rate”?

The amount of revolutions that a baseball spins per minute. The advent of high-motion sensor cameras and radar-based measurements have allowed teams to analyze individual pitches in granular detail while the launch of Statcast has made spin rate more palatable to the casual fan. Ten years ago, spin rate was only discussed among a handful of front offices and baseball junkies. Now, even amateur pitchers obsess over whether their fastball and curveball have enough rpms.

And how does this grip affect spin rate?

If the pitcher has a stronger grip of the ball, then it’s easier for them to throw it in a way that will increase the amount of spin on their pitches – and the movement of the ball through the air.

So if it’s not spit or Vaseline, what is it?

The most popular substance in question is the aforementioned Spider Tack, a rosin-based paste described in its Amazon profile as helping powerlifters “load Atlas Stones,” a signature event in strongman competitions. In a recent Wall Street Journal interview, Spider Tack creator James Deffinbaugh described it as having the viscosity of molasses. He also noticed that sales had increased over the last year and that MLB teams were ordering it wholesale. Other grip enhancers include Pelican Grip Dip – a mixture of pine tar, rosin and pine oil – as well as less sticky stuff like sunscreen.

Wouldn’t that cause the ball to stick to a pitcher’s hand?

That would probably happen if a pitcher applied too much of it, but most players keep dabs of it on the inside of their glove or the brim of their hat. A quick two-fingered swipe is all it takes to apply the sticky, tacky substance. Once it’s on the tips of a pitcher’s fingers, he can apply the enhanced grip that will bolster the spin on the ball.

If it’s against the rules, why does it still happen?

Teams adopted a detente because nobody wanted their pitchers to get caught. Traditionally, MLB has left it to opposing coaches to alert umpires whether they think a pitcher is using a foreign substance. Most managers elected not to so out of fear that it would increase the chances of their own pitcher getting caught using a foreign substance.

Hitters want pitchers to have control – it reduces the chance of them getting plunked in the head by a wild pitch – so they don’t mind pitchers using substances like rosin and sunscreen for a lightly enhanced grip on the ball. As New York Mets first baseman Pete Alonso said: “Whatever they want to use to help control the ball, let them use it, because for me, I go in the box every single day, and I see guys throwing harder and harder every day, and I don’t want 99 slipping out of someone’s hand.”

So what’s next?

It’s hard to tell. There have not been any suspensions, but spin rates of star pitchers like Cole and Dodgers starter Trevor Bauer have declined since the issue started dominating headlines. The difference is substantial: In April, the Athletic documented a difference of up to 500 rpms between pitchers using sunscreen and those using Spider Tack.

Hitters probably want it out of the game, but what if it makes their own pitchers less effective? This one isn’t over yet.