It’s officially been one month since Major League Baseball implemented their guidelines forcing umpires to check starting pitchers for illegal foreign substances. Sure, the All-Star break cost us a few days worth of data points, but in general, we have seen more than enough games, analyzed the spin rate of more than enough pitches, and tallied more than enough batted balls to determine whether or not Spider Tack and other sticky substances were really altering the game of baseball in a drastic way.
Prior to the additions to Rule 6.02 of the official MLB rulebook, the league struggled to get any offense going. The league-wide batting average was .239 — tied for the second-lowest mark of all-time. Hitters were, and still are, striking out more than ever before, and offenses were tallying just over four runs per game. It was a pitcher’s game, and everyone else was just playing in it.
However, since the new rule came into effect on June 21, I’m happy to report that offensive numbers have gone up tremendously. Hitters are slashing .249/.325/.419 over the last 30 days. Each of those stats has increased at least ten points since from where they were on June 21. Home runs are up. Doubles are up, but most importantly, teams are scoring more runs. In just one month without sticky substances, runs per game across the league has skyrocketed from just over 4.2 to over 4.49 for the 2021 season. In the last 30 days, teams have been averaging almost five runs per game. Since June 21, there are 19 teams with a slugging percentage over .400. NINETEEN! There were just ten such teams prior to the rule change.
Is this increase in offensive numbers solely because pitchers have stopped using sticky substances? Not entirely. There are dozens of other factors that could be playing a part in this as well, but it’s surely played a major role. Pitchers wouldn’t have used those sticky substances if they didn’t believe it would drastically help them. Higher spin rates lead to more movement on pitches. More movement leads to more swings and misses, or at the very least, weaker contact. Hard-hit percentages have gone up (31.6 percent prior to June 21 to 32.8 now), but that jump isn’t nearly as big as you’d expect it to be. Even with spin rates down drastically, hitters don’t seem to be making better contact by a wide margin.
And yes, spin rates are down drastically. Per the New York Times, pitches have an average RPM 86 points slower today than they were on June 3rd. That drop-off isn’t normal. Since 2017, the largest drop in RPM over the course of a month has been approximately 20 points. 86 is unheard of, and undoubtedly a huge indicator of how common the use of illegal sticky substances was. Some of the pitchers who have seen the largest drop-offs in RPM are Oakland’s James Kaprielian (-325 RPM), Los Angeles Dodgers’ starter Trevor Bauer (-243), Indians’ reliever James Karinchak (-205), and Yankees’ starter Gerrit Cole (-175).
However, one percent in regards to strikes thrown is a big deal. In baseball, one percent is the difference between a .260 and .270 hitter. One is considered pretty solid, the other is considered pretty average. When hitters make more contact, that leads to more defensive mistakes, lucky bloopers, and overall just more opportunities for offenses to score runs. Not only are hitters making more contact since the crackdown, with fewer pitchers having the control they once had using Spider Tack or sunscreen, they’re seeing fewer pitches in the zone than before. This small discrepancy has created a major ripple effect leading to more walks, fewer strikeouts, and therefore more runs.
As much as we’d like to make fun of pitchers for using illegal tactics to gain an advantage, the data shows baseball’s offensive lull to start the 2021 may have been just as much due to impatient hitters. Now that spin rates are down, hitters are able to see the ball better. As hitters have learned to let a few more go by, sure they might see more strikes, but they’re also forcing pitchers to attack them at the plate. The sticky substances definitely played a role, but was it really big enough to turn the Detroit Tigers into one of the most consistent offensive teams over the last 30 days? They’ve scored the sixth-most runs in the league since June 21. That’s bigger than just sticky stuff. That’s a change to the general approach hitters were taking.
Moreover, if sticky stuff was really the only factor keeping pitchers at the top of their game, then why have several of the pitchers I named earlier who’ve seen tremendous drops in spin rate continued to maintain their dominance without the use of Spider Tack? James Kaprielian had a 2.84 ERA prior to the crackdown while striking out 42 hitters in 38 innings pitched. Since June 21, Kaprielian has 2.40 ERA while striking out 31 in 30. He’s arguably been better. The same goes with Karinchak, who has seen his ERA drop from 2.41 to 1.80 since the crackdown. The only pitcher I mentioned who’s really experienced a downfall is Gerrit Cole (and Trevor Bauer, but he’s been worse because of different issues). However, based on the data, Cole is an outlier, not the pitcher to base statements off of. Did sticky stuff help these pitchers? Absolutely, but they’ll be just fine without it.