Best of BP: The Problem with Blake Snell’s Command is His Approach

Baseball is again. On February 14, pitchers and catchers reported to Spring Coaching, and the reviews of gamers being within the Greatest Form Of Their Life have began pouring in. Absent from these festivities: the reigning Nationwide League Cy Younger winner, who as of this writing continues to be unemployed. A part of that’s actually groups biding their time to maximise their leverage, however a part of it might be that Blake Snell is without doubt one of the harder pitchers in baseball to venture. Leaving apart his well being file for a second, there’s some proof of a weak basis underlying his success. Others have written extensively in regards to the issues behind Snell’s league-leading 2.25 ERA final season, and so they focus on his propensity for giving hitters a free base. Contemplate how our Pitch High quality metrics, which worth a pitcher primarily based solely on the traits of his pitches and never on outcomes, rank him amongst certified starters: Whereas his Stuff High quality ranks thirteenth amongst certified starters, his Total Pitch High quality—which takes into consideration each Stuff and Places—ranks thirty sixth. Put merely, he’s not hitting adequate places to maximise the worth of his stuff.

The place analysts start to disagree is in what’s driving such seemingly poor location of his pitches. Whereas many attribute his walks to poor command, others have argued they’re by design: a worthwhile by-product of concentrating on the sides of the zone and being unwilling to present in and danger laborious contact. The reality is probably going some mixture of each, nevertheless it’s tough to disentangle the 2 with out figuring out the place Blake was concentrating on with every pitch. Fortunately for us, a presentation finally yr’s Saber Seminar by Scott Powers and Vicente Iglesias provided a roadmap for doing simply that. They used what’s referred to as a Hierarchical Mannequin to estimate the common and customary deviation of a pitcher’s pitch places after which simulate new places utilizing these mannequin estimates. Our methodology differs barely from theirs, and although it might sound sophisticated, the overall strategy is intuitive and simple to observe.

We begin by modeling the anticipated horizontal and vertical location of every pitch primarily based on the kind of pitch it was, the depend wherein it was thrown, the handedness of the batter and pitcher, and the id of the batter. Subsequent, we modify these anticipated places primarily based on the overall tendencies of the pitcher.[1]

These anticipated places are handled because the pitcher’s goal for a given pitch. Utilizing these goal places and the precise noticed places of every pitch, we’re then capable of mannequin the common and customary deviation of the space and course of every pitcher’s misses. These common miss distances and places are extraordinarily sticky, with a year-to-year correlation of 0.7 amongst pitchers with no less than 500 pitches thrown. For comparability, the year-to-year correlation of a pitcher’s strikeout fee is round 0.6.

Now that we have now all of those anticipated places and unfold in places for every pitcher, we will simulate new pitches utilizing totally different assumptions. First, let’s simulate a bunch of fastballs from Blake Snell utilizing his personal common goal location, miss distance, and miss course and plot them collectively together with his precise fastball pitch places.

I selected to not label which pitches had been actual and which had been simulated for a cause. Are you able to inform the distinction between them? As a result of I positive can’t.[2] Subsequent, let’s simulate one other set of fastballs, however this time we’ll use a mean pitcher’s unfold in miss distances to see how that compares to his personal unfold.

Right here I’ve plotted the simulated pitches from Snell’s personal miss distribution in blue and from a mean pitcher’s miss distribution in crimson. Be aware simply what number of extra pitches find yourself out of the zone (usually far sufficient out to qualify as waste pitches), indicating that no matter the place Snell is concentrating on, he’s struggling to hit his spots relative to a mean pitcher in the identical eventualities. And it’s not simply his fastball. Amongst 479 pitchers who threw no less than 500 pitches in 2023, Blake Snell’s common miss distance ranked 425th. Rating one level to the command camp. However earlier than we declare a winner, let’s additionally take a look at his anticipated goal places.

This time we’ll take a look at Snell’s slider, and as a substitute of a scatter plot of particular person pitches we’ll plot a contour of his places with a marker for his typical seemingly pitch goal and the place a mean pitcher would have focused those self same pitches given the context.

That roughly six-inch distinction in targets takes a variety of what can be well-located chases down and away and turns them into straightforward takes for a ball. Positive, it might save him from some laborious contact however, when your slider generates whiffs in addition to his, I see no cause why he ought to be losing them out of the zone. He ought to be difficult hitters and daring them to place a barrel on it.

So we’re again to the place we began, with each the “poor command” and the “poor strategy” camps having loads of proof for what led to Snell’s abundance of walks, albeit we now have the beautiful plots to again all sides up. The pure follow-up is: Which is hurting the worth of his pitches extra? To guage this, we will feed all of our simulated pitches into our Pitch High quality mannequin. We’ll begin by simulating a full season of pitches from Snell utilizing his personal targets and miss traits. Then we’ll simulate a season utilizing his personal targets however a mean pitcher’s miss traits. Lastly, we’ll simulate a 3rd season utilizing his personal miss traits however a mean pitcher’s goal for every pitch. The variations between the fashions ought to reveal whether or not his command or his strategy was having a bigger influence on his anticipated pitch worth.

Our modeled simulations discover that if Blake Snell had been to enhance his command to that of a mean pitcher, the anticipated run worth of his pitches would enhance by a little bit greater than half a run per 100 pitches. If as a substitute he had been to maintain his identical command however merely goal areas extra typical of a mean pitcher, his anticipated run worth would enhance greater than three-quarters of a run per 100 pitches. The command could also be dangerous, however the strategy seems to be even worse.

To grasp why the fashions present such discrete variations in predicted worth, we will look deeper into the anticipated outcomes of every pitch from the separate fashions. Beneath I’ve added a column for the anticipated distinction in worth of balls in play, distinction in swing fee, and distinction within the variety of balls thrown between every of the fashions.

To others’ factors, a change in command or in strategy for Snell would depart extra balls over the center of the plate, resulting in each extra contact and extra laborious contact. Over a full season, the mannequin believes that this may value Snell almost 9 runs in worth if he had common command. Nonetheless, this influence is swamped by what number of fewer balls he would throw as a result of change, leading to each fewer walks and fewer favorable counts for the hitters.. The mannequin discovered {that a} change in command would lead to a rise in swing fee of eight p.c and a lower of 361 balls thrown. For a change in targets the variations had been 4 p.c and 205, respectively. He’s higher off attacking the zone and accepting the occasional laborious hit ball than he’s nibbling and racking up walks.

The query for a group seeking to signal Snell is twofold. One, is there some worth to his strategy that our Pitch High quality fashions are lacking? Given the spectacular correlation between the mannequin predictions and the noticed final result of pitches, we discover this unlikely. Which results in the second query: is Snell open to a change in strategy? If Snell had been an up-and-coming rookie it will not be a lot of a query. However we’re speaking a few 31-year-old established veteran with two Cy Youngs beneath his belt. I can’t say that I’d be amenable to altering a single factor had been I in his footwear. Possibly his uncooked stuff will proceed to hold him, however velocity doesn’t final ceaselessly. Sooner or later, Blake Snell goes to wish to make a change, and it begins with throwing strikes.

[1]For the nerds: I used MAP estimates of the imply from a multivariate-normal hierarchical mannequin in pymc. The mannequin was structured such that international means had been estimated for every mixture of pitcher handedness, batter handedness, pitch sort, and depend. Then, particular person means had been estimated for every batter and every pitcher ID primarily based on pitch sort, platoon benefit, and depend.

[2] Blue dots are simulated.