Gary Sánchez Is Due for an Improved 2021

After Gary Sánchez’s rough 2020, there’s pretty much nowhere to go but up.

That was the rationale for including him among the 2021 ZiPS breakout candidates, with Dan Szymborski noting that no big league hitter — especially one with Sánchez’s power pedigree — carries a true-talent .159 BABIP. Unfortunately for the Yankees’ backstop, that’s how his batted ball luck shook out, with the shortened 60-game season preventing his BABIP from ever regressing to the mean.

Granted, Sánchez was not the only hitter to face extremely poor batted ball luck. A perusal of all players with at least 100 trips to the plate last season shows us that Sánchez only posted the fourth-lowest BABIP in the majors, with Hunter Renfroe (.141), Edwin Encarnación (.156), and Rougned Odor (.157) all worthy of taking even more issue with the BABIP Gods.

But even compared to these other tough luck seasons, Sánchez sticks out. What caused him as much trouble, if not more, was a lot of swinging and missing, something he did considerably more often than most of his peers in the bad BABIP department, with strikeouts in 36% of plate appearances. That combination of poor BABIP and a low propensity to put the ball in play resulted in a career-worst .147/.253/.365 triple slash.

Things are already different, though, in 2021, with Sánchez homering in each of the Yankees’ first two games and not striking out once. That latter feat — back-to-back games without a K — is something he did just once last year. That’s not to say he won’t strike out quite a bit this season. He’s whiffed four times in 16 plate appearances so far and struck out 20 times in 48 spring plate appearances — the latter an ugly 42% strikeout rate. And before you say “spring training stats don’t matter,” a study from Dan Rosenheck at The Economist showed that a hitter’s strikeout rate from spring training correlates well to his regular-season mark. Even still, Sánchez doesn’t need to eliminate the strikeouts to be successful. Even in the two separate seasons where he struck out at least 24.9% of the time, he still posted a wRC+ of 115 or better.

What’s more important for Sánchez is a reversal of his batted ball luck, but it’s not quite as simple as that. We need to take a deeper look at where BABIP comes from, and also why we can expect Sánchez to post a better one.

Bat control, measured by analysts as the standard deviation of a player’s launch angle on their batted balls, correlates well to BABIP. Looking at hitters from the 2019 season, we can model BABIP based on two simple inputs: average launch angle and standard deviation of launch angle. While BABIP is still luck, shift, and speed driven, this simple quadratic model results in an r-squared of 0.37 among hitters who put at least 250 balls in play:

Some selection bias must be acknowledged here, as a lot of these statistics take time to stabilize, which has an influence on the model. But it is also a solid proxy for a big league regular during a normal season, considering the sample size of 225 suggests that, on average, 7.5 players per team would qualify under these stipulations.

What does this mean for Sánchez? First, his bat control actually improved in each of the last three seasons, even as the average standard deviation of launch angle increased league-wide. (This is due to MLB’s switch from Trackman to Hawkeye technology for Statcast.) If we standardize his sd(LA) over the course of the last few years, we find that the improvement is much more stark than a simple look at the raw figures:

From this, we can retroactively model what Sánchez’s BABIP should have been last year. The regression won’t work perfectly, since 2020 was anything but a normal year, but it makes sense to use a model from 2019 given that the 2021 baseball season should look more like ’19 than ’20.

Here are Sánchez’s regressed BABIPs, based on his standardized sd(LA) and average launch angle:

Even accounting for the relative uncertainty of the model, Sánchez’s 2020 BABIP was 74 points worse than even the lower bound of the 95% confidence interval. That’s not to say he’d magically post an elite slash at a .233 BABIP. But even if we assume that all of the additional hits he’d produce at that BABIP would be singles, a .186/.304/.404 slash line gives him nearly 90 additional points of OPS from his actual 2020 figure.

There were other holes in Sánchez’s game last year, with strikeouts chief among them. Plus, as Lindsey Adler and Eno Sarris explained at The Athletic, his lack of speed limits his upside and could be a reason to predict lower-than-expected BABIPs going forward. Still, it is pretty evident that luck played a huge role in Sánchez’s poor 2020. Given that his bat control has only improved and that his power remains elite, it’s hard not to expect much more from him in 2021. His solid start in the first weekend might only be a sign of what’s to come.