Even before those numbers came to light, an avalanche of criticism thundered toward the veteran umpire. A pair of strike calls by Kulpa at the expense of David Ortiz turned a potential game-tying walk into a pivotal strikeout in a 3-2 Yankees win. The first came on a pitch where catcher Brian McCann’s glove crisscrossed the plate. The second came on the next pitch, one so low — ESPN Stats said it was 5½ inches below the strike zone — that Sox manager John Farrell suggested his DH would have needed a hockey stick to hit it.

That number floated through an incredulous Red Sox clubhouse last Saturday morning, the published claim by ESPN Stats & Information that on Friday night plate umpire Ron Kulpa had missed 31 calls — with six other games having featured worse results this year.


A review of the game data by TruMedia Networks, an analytics company that evaluates the probability that any caught pitch will be called a ball or strike, revealed that the first disputed pitch is actually called a strike 94 percent of the time; it merely looked like a ball because of the drastic movement of McCann’s glove.

The second disputed pitch, however, was measured as approximately 4½ inches below the strike zone, a pitch that is called a strike just 1.6 percent of the time. Overall, according to the company’s model, Kulpa added an estimated 9.6 strikes above an average strike zone, with 6.6 coming at the expense of the Red Sox and 3.0 coming against Yankees hitters.

The addition of 9.6 strike calls above average defined the game as the seventh-largest strike zone of the year.

Kulpa’s interpretation — coupled with what the Red Sox viewed as baiting the slugger with a staredown and smirk as he returned to the dugout — lit a fuse that resulted in ejections of both Farrell and Ortiz, not to mention controversy.


Twitter glowed with exhortations to fire Kulpa. Yet some offered more far-reaching cases to alter his job fundamentally, viewing his poor showing (a departure from relatively solid grades on ball/strike calls throughout his career) as yet another log on the fire in the case for MLB to automate its strike-zone judgments.

Players skeptical

For most players, the idea of automating the strike zone represents a sort of third rail they’d rather not breach — even after a game like Friday’s. Objections took a few forms.

“Robots?” Red Sox second baseman Dustin Pedroia said suspiciously when asked about an automated strike zone. “Come on, dude. We’re playing baseball. It’s part of the game.”

“I’m kind of anti-changing the game too much,” said Sox righthander Rick Porcello. “I love this game for what it is — good or bad. You roll with the breaks you get and the ones you don’t get.”

“That’s what makes the game so great,” Farrell said. “There’s always going to be a human element involved.”

There are also concerns about the ability of a pitcher and catcher to execute borderline pitches with such skill that they effectively expand the strike zone. It is considered one of the game’s great skills.

“Being a pitcher, there are pitches I get that weren’t as bad [as the ones Kulpa called] that, if it was automated, I wouldn’t get,” said Sox righthander Clay Buchholz. “And the catcher framing the pitch would be obsolete. That wouldn’t be considered something a catcher can do better than other guys.”


Additionally, there were claims that the technology to automate strike-zone calls doesn’t exist. Whereas tennis has been revolutionized in part because computers can examine the ball precisely relative to a court with fixed dimensions, baseball’s strike zone shifts from batter to batter in a way that could make it more challenging to automate.

“We don’t have the technology. That [strike zone] box is the same size for David Ortiz as it is for me and he’s a foot taller than me,” said Pedroia. “The last pitch on David that’s not even close to being a strike, that’s a strike on me. But the box is going to say it’s a ball.”

Or is it?

A Pacific view?

In many ways, Eric Byrnes is the most visible apostle of the automated strike zone. The ability of umpires to influence games is one about which the 11-year big league veteran — now an MLB Network analyst — feels passionately.

“Everyone wants to say, ‘What about the human element?’ The human element has been and always will be the players. It’s not about the umpires. The best umpires are the ones you never notice,” said Byrnes.

“With a Las Vegas betting line, the three most important people in the game are the two starting pitchers and the home plate umpire. If that’s not garbage, I don’t know what is.

“The bottom line is this: Any baseball fan could watch what happened [Friday] night and know that neither one of those pitches was a strike,” he continued. “These guys are human. I’m not going to go as far as to say that Ron Kulpa had it out for David Ortiz. I don’t know that. But the problem is that umpires even admitted — former umpires; I don’t know if current umpires have — former umpires admitted to me that they make makeup calls, they made calls because of personal vendettas. To think that we have the game decided by an umpire . . . ”


In an effort to counter such a possibility, last summer Byrnes oversaw a two-game trial of an automated system by the independent league San Rafael Pacifics. The Pacifics employed the same PITCHf/x system used both on MLB.com’s GameDay and by MLB for umpire evaluations, with an on-site technician adjusting the strike zone from at-bat to at-bat based on hitter heights and stances — the very adjustments with which Pedroia was concerned.

Eric Byrnes used a computerized video system to call balls and strikes at an independent league game in San Rafael, Calif. Eric Risberg/Associated Press/File 2015

Byrnes sat behind the plate looking at a monitor and announced into a microphone whether pitches were balls or strikes, based on whether the screen flashed (strike) or didn’t (ball). The plate umpire didn’t have to worry about balls or strikes, instead focusing on the other aspects of his job.

“[The plate umpire] personally came to me and said, ‘Eric, I’ve got to tell you, I was obviously — just like every umpire in the world — very skeptical of what you were trying to do today. I’ve never felt more dialed in to all the other things that home plate umpires need to worry about. I loved it, because I knew that I got every call right,’ ” Byrnes relayed.


The technology isn’t perfect. PITCHf/x has a margin of error of up to about an inch — though as Byrnes notes, that pales in comparison to a call that misses by nearly six times that amount. Byrnes suggests that while umpires will be skeptical of potential job loss from a change, crews could be expanded not just to preserve a plate umpire responsible for all calls not related to the strike zone, but also a fifth member who would work with a technician on the strike zone and also provide an on-site arbiter of other plays subject to replay.

Redefining the zone

This graphic shows the pitches in David Ortiz’s last at-bat Friday as recorded by MLB’s Pitchf/x system. Tonia Cowan/Globe Staff

For now, there’s no evidence that Major League Baseball is considering either the automation of the strike zone or the expansion of replay to include challenges to ball/strike calls (an in-between solution endorsed by Red Sox bench coach Torey Lovullo). Commissioner Rob Manfred said at last summer’s All-Star Game that the sport wasn’t at the point of considering an automated strike zone.

Meanwhile, the idea of implementing an automated strike zone would be complex. There’s a very good chance, for instance, that the league would have to redefine the strike zone, given that the rule book zone would expand strikes vertically to the point of creating an offensive ice age.

There are numerous factors that likely will result in a glacial pace in the consideration of change. After all, Byrnes noted that 28 years passed between when Don Denkinger’s blown call likely changed the fate of the 1985 World Series and the implementation of the current system of replay.

Still, the job of umpires is getting continually harder. The higher velocity of pitches and the extraordinary movement and deception that is employed with the intention of rendering it difficult for hitters to determine what constitutes a ball and strike doesn’t magically go away for umpires. Umpires are grading extremely well in the eyes of baseball, with accuracy percentages typically in the low- to mid-90s for balls and strikes (with a defined margin of error that is the width of a baseball), but as Friday showed, there’s room for improvement.

Byrnes plans on another experiment this summer, using the same system but with Byrnes serving as plate umpire, where he’ll be told through an IFB earpiece whether a pitch is a ball or strike — thus maintaining the appearance of the ball/strike call.

Such experiments are necessary to help decide whether baseball will alter the way that its most fundamental element — the shape of the strike zone — is judged.

“The technology is out there. Is it absolutely, 100 percent perfect? No. But the technology is good enough for Major League Baseball to use the PITCHf/x technology to grade and judge major league umpires on a nightly basis,” said Byrnes. “If you told me it was 20 years away, I would honestly be disappointed but I wouldn’t be shocked. If you told me that it was five years away, I would think that is very realistic.

“Baseball needs to utilize the technology that is available. Why in the 21st century, when we have all this great technology at our fingertips, are we not using it?”

Alex Speier can be reached at alex.speier@globe.com. Follow him on Twitter@alexspeier.