Against Robot Umpires

Last night in the independent Atlantic League, “robot umpires” took the field for the first time. It was a vicarious takeover: Home-plate umpire Brian deBrauwere wore an Apple AirPod, which relayed to him the ball–strike call, which was made by an on-site computer. A few seconds later — sometimes with a noticeable delay and an awkward hesitation — deBrauwere would announce the computer’s call himself.

The Washington Post’s headline following the Asimovian display: “‘Robot ump’ calls first professional baseball game with one hitch and no controversy.”

No controversy! Allow me.

In much the same way the baloney abhors the grinder — to borrow from William F. Buckley Jr. — the former catcher in me loathes the thought of “robot umpires” displacing their human counterparts. Sabermetric analysis reveals the startling defensive value that catchers add by their “pitch framing” prowess — what some catchers call “receiving,” or “presenting” the pitch to the umpire. That’s value that, if lost, would deal yet another blow to baseball’s most grueling and thankless position. But even aside from special pleading for those wielders of the tools of ignorance, there is the problem that a robotic strike zone would eliminate a distinctly human reprieve within a mechanistic and data-soaked sport; that timeless interplay between catcher, umpire, and pitcher would cease, ceding to the same soulless impulse of revolution overtaking America’s other professional sports.

Baseball’s would-be innovators are unpersuaded, I’m sure, by my romantic longing for what they see as the needless glorification of human error, and by the bastardization of the strike zone to fit the distortion and biases of the human eye. But the game of baseball would itself be losing something profound were it to adopt a robotic strike zone.

First, on a practical level, the technology isn’t fully there. The computerized zone, by the league’s own admission, isn’t perfect yet. The automated zone still has struggles with backdoor sliders and late-moving breaking pitches, and, as was on display in the Atlantic League game, there are still mechanical hiccups and delays with the technology. All this as human umpires themselves are becoming more accurate: A 2019 Boston University study estimated that home plate umpires made the proper ball–strike call 90.79 percent of the time in the 2018 season. The league average has improved every year since 2008, and the youngest umpires are among the most accurate, meaning league-wide accuracy rates will likely continue their ascendant trajectory.

Next, MLB’s rulebook definition of the strike zone is necessarily subjective in its constitution. The zone extends from the approximate center of the batter’s torso to the bottom of the knee — this is crucial — “as the batter is prepared to swing at a pitched ball.” This addendum is meant to incorporate the peculiarities of player batting stances while also defining the precise moment at which a player’s stance becomes his attempt to “swing at a pitched ball.” Each iteration of the automated strike zone (from Pitch F/X to the new TrackMan software) requires some third party — whether it be a ballpark “stringer” calibrating the zone at the park or something embedded into the software — to make the subjective “prepared to swing” determination. That judgment is just being passed up a level, from an on-field human umpire to some other third party.

But there is no doubt that the automatic zones, whatever their current shortcomings, are more “accurate,” to use a loaded term, than their human counterparts. The larger question, then, is how much accuracy fans are willing to trade for the sport’s aesthetic continuity, human element, and dramatic interplay.

There’s something poetic about the game of baseball. Whether you’re watching Georgia’s Baldwin High School Braves or the Atlanta Braves, there’s a noticeable congruity — both games involve the same basic dynamics, the real-life (if unintentional) human drama between player and official. If MLB were to implement robotic strike zones, it would stratify itself not only by talent but also by content: There would be a marked, fundamental difference between the game played by Baldwin High School and its home state’s professional team. To some would-be revolutionaries, this is a positive development — the Boston University study balked at the notion that “umpires continue to call balls and strikes like they did 100 years ago when Babe Ruth reigned supreme and the Ford Model T ruled the roads.” To others, myself included, this is a feature rather than a bug — Babe Ruth, the Baldwin High School shortstop, and Ozzie Albies all play by the same rules, more or less, keeping alive the glorious intergenerational continuity that makes baseball America’s pastime.

G. K. Chesterton once quipped that it is “mysticism” that “keeps men sane.” If our sports are to become hyper-rational institutions, devoid of that most basic human drama that draws us to sport in the first place, haven’t we lost something?

Let the catchers keep framing pitches, for goodness’ sake.