Donovan Solano Has a Weird Shadow
In some ways, Donovan Solano is lucky. For the past two seasons, he’s racked up a well-this-won’t-last BABIP of .403. When we speculated the potential rise of a .400 hitter in a pandemic-shortened season, Solano became an unlikely candidate, outpacing pre-season favorites like Cody Bellinger and Christian Yelich. While his production declined as expected, he certainly left an impression on many, myself included.
In other ways, however, Donovan Solano is unlucky. What began as an investigation into whether Solano can maintain some of his BABIP luck morphed into something far more intriguing. Though he fell short of his one-in-a-hundred shot at eternal baseball glory, he did experience a statistical quirk that is of equal probability: When it comes to borderline strikes, Solano was one of the unluckiest hitters in Major League Baseball.
Whew, that’s quite a thesis. But let’s take a step back here to clarify what I mean by borderline strikes. On Baseball Savant, the area surrounding home plate is divided into four regions: the Heart, Shadow, Chase, and Waste. Pitches located in the Heart are down the middle. Both pitches in the Chase and Waste regions are balls. And pitches in the Shadow are a bit ambiguous — depending on various factors, they can either strikes or balls. They’re tricky, so hitters tend to struggle the most with them.
Now, imagine taking a pitch that lands in the Shadow. What percent of the time would it be called a strike? If your guess is 50%, that’s a great one. From 2019 to 2020, pitches taken in that region were called strikes 48.4% of the time. Most hitters’ CS% (called strike rate) fall in between 44% and 52%. Donovan Solano, then, might surprise you. In that same window of time, he took 295 borderline pitches. 182 of them were called strikes, for a rate of… 61.7%. Does that seem like an outlier? You bet. In fact, amongst 368 hitters who took at least 200 borderline pitches between 2019 and 2020, Solano is at the very top. Note that the denominator consists of only taken pitches, not total pitches:
Convert Solano’s Z-Score into a percentile, and you get a whopping 99.92. In 295 coin flips, Solano’s coin landed tails 61.7% of the time. This is an aberration that would ruin a casino. In some parallel universe, he might have been a jackpot winner. But because we exist in one in which he’s a professional hitter, he struck out a ton instead.
This is weird, alarming, and fascinating. How do we make sense of it?
The Shadow region is quite expansive, so let’s break it down. There’s the top of the strike zone (Zones 11, 12, 13), the outside edges to RHH like Solano (Zone 14), the inside edges (Zone 16), and lastly the bottom of the zone (Zones 17, 18, 19). By examining which subdivisions contributed the most, or least, to his overall CS%, the hope is to identify the source of his woes. And by using the league-average CS% as comparison points, we can also see if his high rates are anomalies, or rather representative of the league’s current state — in other words, normal:
On pitches located in the bottom of the zone, Solano’s CS% is nothing out of the ordinary. At 37.1%, it’s about the league average. In all other zones, however, Solano seems to be experiencing rotten luck. Check out his CS% rate on pitches up in the zone, which is nearly twice the league average. What’s even more fascinating is that, in most cases, catchers have a hard time framing high pitches — it’s difficult, and umpires don’t acknowledge their efforts. Something else, something not obvious, has perhaps been inflicted onto Donovan Solano.
At the same time, these results can make sense. The coin flip analogy from earlier is imperfect because it assumes that Solano himself is doing the flipping. In baseball, however, that task belongs to the pitcher. What if Solano’s misfortune can be explained by the fact that he’s seeing good pitches? After all, he plays in a division that’s home to Clayton Kershaw, Zac Gallen, and Germán Márquez, to name a few, who all possess excellent command. That isn’t his fault, of course, but it at least provides a reasonable answer.
It’s time to get precise-er. As a first step, I determined the boundaries of Solano’s personal strike zone. While using a standard strike zone is easier, that doesn’t account for the fact that Solano, who’s listed as 5-foot-8 on Baseball Reference, is one of MLB’s shorter hitters. Calculating width is simple, at least. The plate is 17 inches wide, to which I added half the diameter of a baseball (2.94’’/2) on both sides, since pitches don’t have to be completely within the zone to be legitimate strikes. Height is a bit trickier, but I think this method is reasonable: When a pitch is halfway to home plate, a Pitchf/x operator determines the upper (sz_top) and lower (sz_bot) bounds of the current batter’s strike zone. It’s their method of recording strikes and balls. A problem with sz_top and sz_bot is that they vary even within the same at-bat, sometimes to a fault. But using the average of a large sample, we can reasonably judge the height of a certain batter’s zone. As with width, I also added diameters-and-a-half to Solano’s sz_top and sz_bot.
Basically, if we know what Solano’s zone is like, it’s easy to figure out what his CS% rate should have been — just toss out the pitches that aren’t within the acceptable dimensions. Below is a table comparing Solano’s actual CS% to his ‘deserved’ CS%, which hopefully gets us closer to an answer:
Across the board, Solano experiences a drop in CS%. I should note, however, that some of these differences are more drastic than they seem due to sample size. For example, the change to Zone 14’s rate is a result of just five stray pitches, not dozens. Still, the drops suggest that Solano is a victim of luck rather than good pitches — had the latter been true, we would expect his Deserved CS% to resemble his Actual CS%. Often, outliers are outliers for no particular reason.
There’s one piece of the puzzle that’s missing, though. Even after adjusting for the uniqueness of Solano’s zone, his CS% on high pitches is still substantially above the league average. What gives? Maybe Solano did face good pitches located there, hence the abnormal rate. But while doing research, I stumbled upon a more interesting theory that requires a bit of explanation. When Donovan Solano first steps into the batter’s box, he assumes an upright stance:
Then, as the pitch is released, Solano lowers himself into a more crouched position:
What does that have to do with called strikes? Back in 2018, Nate Freiman wrote for FanGraphs about the relationship between height and a batter’s strike zone. In his article, Freiman dove into the case of Hunter Dozier, whose 13.0% rate of high-pitch strikes was far above the rest of the pack. The theory: Dozier — who starts off tall then sinks into his knees, just like Solano — throws off strike-zone coding and the perception of umpires. Since sz_bot or sz_top doesn’t change once set, sudden movement of the upper body could create an inaccurate representation of Solano’s or Dozier’s strike zone.
In addition, umpires might not buy into the idea of a mid-pitch stance change. Believing that hitters like Solano are forcefully trying to create an advantage by shrinking their zones, they could be more inclined to award balls and strikes based on their original, more upright postures.
But if I’m being honest, the biggest factor is probably sample size. Change the requirement from earlier to min. 400 pitches, and we’re left with Jose iglesias (60.1%). Crank it up to min. 750 pitches, and the highest rate belongs to David Fletcher (52.9%). It’s plausible that a hitter’s CS% rate on borderline pitches regresses itself towards the 50% mark over the course of hundreds, if not thousands of pitches. With just 295 takes so far, the verdict on Solano is unclear. We’ll have to see what happens in the 2021 season, as he’s projected to appear in 112 games, per ZiPS. That’ll give us a better sample size to work with.
Regardless of whether this is meaningful or not, it’s always fun to pull back the curtains on an outlier and attempt to comprehend him, especially someone who’s as out-there as Solano has been for the past two years. Beneath a career strikeout rate of 17.8% against a walk rate of 5.3% lies an unthinkable 61.7% rate of failure against supposedly borderline pitches. Who knows, he might have a better eye than we give him credit for.
All data courtesy of Baseball Savant and FanGraphs.
