A sticky situation: MLB will monitor spin rates via Statcast in 2021

Late Tuesday night Joel Sherman at the New York Post reported that MLB will issue a memo to teams that the league will begin monitoring Statcast data to identify pitchers who are tampering with the ball. I immediately started thinking about the Houston Astros.

I have poked fun at my own “worst take” a few times now, but it’s relevant to this story so let’s revisit the time I said the Cubs should not trade for Justin Verlander because his stats looked a lot like John Lackey’s. Within a month of writing that piece a really funny thing happened. The Astros traded for Verlander and he went from looking like Lackey to pitching better than he had in his career to date.

Look, the predictions business is fraught and based on the data there were a lot of reasons to have doubts about Verlander. I wasn’t alone, Paul Sporer at RotoGraphs was skeptical too:

It seems as if his stuff isn’t as sharp as it was last year with the fastball being the chief offender. Now the real question is whether it’s a flat out degradation of the stuff, injury, or something fixable that requires a tweak or two to get him on his way. Major control issues can sometimes be a precursor to elbow injury so I can’t ignore the jump from 6% to 10% in walk rate. For now, I’m holding on with Verlander, but I can’t see enough to encourage an active buy for me.

But when Verlander got to Houston it was like a switch flipped. All of his pitches were immediately more effective. Turnarounds like this are rare, I mean just look at this:

FanGraphs

FanGraphs

It was a remarkable (and rare) feat for a pitcher to magically flip a switch and be better than he’d ever been at age 34. But there were no two ways around it, Verlander had somehow figured out how to be more effective at 34 than he was at 24. More effective at 35 than he was at 25. You can see it clearly. And it wasn’t just Verlander — Gerrit Cole immediately transformed into a fundamentally different pitcher with the Astros after the Pirates traded him there:

FanGraphs

FanGraphs

Now, ERA is imperfect and the 2017-19 Astros were certainly better defensively than the Tigers or Pirates, but walk and strikeout rates aren’t impacted by defense, so clearly something else was going on.

Enter, stage left, Trevor Bauer.

I want to pause here to caveat clearly that this piece is not an endorsement of Bauer. His reputation precedes him and don’t even get me started about him throwing Spring Training games with one eye closed because he thinks the challenge makes him better or something.

He literally hit a batter with this “experiment” and that batter is lucky he didn’t miss on that pitch in a worse spot. Potentially injuring someone because you think it’s a fun trick to close one eye while hurling a rock 90 miles per hour in the general direction of someone else is never cool.

That said, Bauer is known for experimentation and one of those innovations is the reason we know fairly definitively that there is a way to magically become more effective as a pitcher. It turns out using certain substances when pitching can have a dramatic effect on pitcher’s spin rates, as Bauer himself explained three years ago:

Speaking of, let’s take a peak at Bauer’s year by year spin rates:

Baseball Savant

Baseball Savant

There is a clear spike in the spin rates on Bauer’s fastball and breaking pitches in 2020 after a slight uptick in 2019. Incidentally, late 2019 and 2020 are Bauer’s most effective seasons as a starter. But before we take a look at some other pitchers, I want to share two quotes from the piece from Eno Sarris in the Athletic that started this whole story. The first is that pitchers using junk on the ball is the worst kept secret in baseball:

It’s an open secret inside the game: Pine tar, and other grip substances, can help a pitcher increase their spin rate. I’ve been asked not to write about it by more than a few pitchers, but at this point there are two pressing reasons to have this discussion.

The second is that a trend of increasing spin rate by itself is not a red flag, the magnitude of that change matters. Spin rate, like a lot of stats, exists in a sort of range. At the risk of revealing my current FitBit data obsession, it’s sort of like how your resting heart rate is stable within a band of outcomes. You should pay attention to it when there are peaks or valleys +/-10 beats per minute but a beat here or there is just noise. Again, here’s Sarris on when those changes matter:

In order to see this possible effect, I looked up the spin rate of all pitchers before they got to Houston, and then once they joined the team for more than 20 innings. Pitchers who were with the Astros before they left weren’t counted, because presumably they could have taken the trick with them to their new team.

On aggregate, the change in spin is tiny. The changes to Justin Verlander’s spin are not significant. Charlie Morton’s spin increase is interesting, but spin is related to velocity, and when Morton’s velocity was up in his abbreviated season with the Phillies, his spin rate was also up. So really, his spin was up to around 2200 right before the Astros picked him up.

Gerrit Cole? Yes, his spin change is remarkable. His release point is up a bit, his velocity is up a bit, and there’s a chance these things are related to spin, even if Bauer and Driveline have tried repeatedly to prove those links in a lab situation but have not yet done so.

As an aside, It is truly a bummer that I am going to have to keep looking for what turned Justin Verlander into an age-defying wizard, but I’m going to continue to include him in the Houston data for comparison sake nonetheless. I think it’s a useful comparison for viewing the magnitude of changes we should be keeping an eye on, and which we should not.

Now let’s take a look at a handful of Houston pitchers Bauer was ostensibly concerned about when he started experimenting with pine tar in the first place, starting with his UCLA rival, Gerrit Cole:

Baseball Savant

Baseball Savant

It is tempting to chalk this up to a college rivalry and call it a day, after all, Tom Verducci characterized the relationship between Bauer and Cole as follows in Sports Illustrated:

So here you have Bauer—the ultimate spin nerd, with his own Trackman system, his devotion to understanding the physics and biomechanics of pitching—and no matter what he does he is stuck with average spin on his heater.

And now here is Cole, his college teammate and apparent rival, who never spun the ball as fast he does, and suddenly he is zooming past Bauer in four-seam spin rate. Apparently from such discoveries are Twitter wars born.

But this is a lot more than a Twitter war. Take a look at another highly effective Astro, Ryan Pressly:

Baseball Savant

Baseball Savant

And now, operating as our age-defying control, here are the same chart and table for Justin Verlander. First of all, yes, it goes up. But it goes up when Verlander is still in Detroit and he’s recovering from surgery to his core (per the Tom Verducci piece above). Without 2015, Verlander’s spin rate would operate in a band much closer to career norms. The slope of Bauer, Cole and Pressly’s line are all forcing a higher Y-axis for them in a way Verlander 2016-2020 would not:

Baseball Savant

Baseball Savant

The bottom line is that the two highest-paid pitchers in baseball have pretty suspect spin rate jumps. Cole, when he was traded to the Astros. Bauer, when he was in his contract year and trying to best Cole. Admittedly, I focused on Astros pitchers here, but the only other pitcher who really caught my eye was Pressly, so with MLB taking a closer look at spin rates, I imagine that will catch their eye too.

Of course, this may just all be much ado about nothing. MLB issues memos and investigates things all the time and doesn’t find anything, even if there is data to the contrary. They investigated the baseball, twice, before finally admitting they were tweaking it and would deaden it for 2021. They investigated the Astros and Red Sox sign stealing scandals and half the people who were suspended due to those investigations have new jobs. Oh, and let’s not forget, they are still investigating Mickey Callaway, more than seven weeks after the Athletic’s Britt Ghiroli and Katie Strang detailed allegations of his lewd behavior towards women during his time with multiple teams. It is highly possible some of these pitchers might be in the Hall of Fame before this investigation turns up anything at all.