I was at a sabermetric conference in Cambridge last August watching a physics professor, Alan Nathan, give a presentation on the possibility of a juiced ball in major league baseball, when around Slide 16, I found myself in a near-frenzy of intrigue and excitement.
Nathan, perhaps the world's foremost authority on the physics of baseball, had shown that the power spike over the previous year -- a spike that has continued this year with record numbers of home runs being hit -- could be traced mostly to increased exit velocity on fly balls. In other words, it wasn't atmospheric factors such as weather, it wasn't that batters were hitting more fly balls, and it wasn't that some fluke number of fly balls were just making it over the wall instead of just shy of it. The ball was traveling faster off the bat, with the change coming almost overnight the previous summer, right around the time some teams reportedly got fresh supplies. It seemed it must be the ball. There was no other reasonable explanation.
It's a thrilling thing, the feeling of believing in a conspiracy. There's a rush in realizing that heavy forces might be running the world but that we are on to them. It gives us a sort of empowerment that we wouldn't feel if we accepted that the strongest forces in the world are actually random, unpredictable, uncontrollable and undesigned.
At the Hardball Times last year, Jack Moore traced the first juiced-ball conspiracists to 1921, and over the past three decades especially, the theories have been accelerating. Not all conspiracy theories are crazy: In 2013, the Japanese baseball commissioner resigned in scandal after the league was caught secretly using a livelier ball.
Here's the key: That commissioner, Ryozo Kato, was punished for his secrecy; two years earlier, the ball was changed to make it more like the one used in American baseball, and it was made openly with no accompanying scandal. If there's a lesson here for MLB, it's this: Quit being coy. Just juice the danged ball!
Or unjuice it. Juice it one year, and unjuice it the next. Do it all the time if it's good for the game. Do it every Monday. Just do it publicly.
Major League Baseball, and its individual clubs, have always taken an active role in preserving an equilibrium on the field, and they've done it openly. The league periodically makes official changes to the strike zone, it periodically sends umpires directives to adjust their de facto zones more closely to the rulebook, and it uses its own technology to enforce the strike zone it wants to see. Teams periodically change their ballparks to make them more hitter-friendly or pitcher-friendly. These are done openly. They are not scandals. They might be debated, but they are widely acknowledged to be within the league's or the team's purview.
The ball is, too. The Rockies, and soon the Diamondbacks, put their baseballs in a humidor to make them not travel as far. Now, imagine if they did this without telling us. Imagine if the league were systematically doctoring baseballs to affect how many home runs were hit. Imagine further if only certain teams in certain ballparks were doing this. It'd be quite the exotic conspiracy theory. You'd sound insane trying to convince somebody it was happening, and you'd have a scandal somewhere south of the steroids era but north of Deflategate if it were found out. But the humidor can't get "found out," because it's not a secret. It's right there. There are press releases. We all know, we accept it and we forget even what a fundamentally weird thing it is to store baseballs in a humidor to make them travel not as far.
Two years ago, the NCAA "juiced" its baseball. After new bat regulations deadened offense in the college game, the NCAA introduced baseballs with flatter seams, which travel farther. It worked. People liked the NCAA manipulating the equipment to maintain an equilibrium between offense and defense. There was no secret, and there was no scandal.
I no longer think that MLB has juiced the baseball; it's possible, but less than likely. By the time I saw Slide 16 in Nathan's presentation, a year's worth of circumstantial evidence had been pointing to a juiced baseball. But in the year since, the circumstantial evidence has been going the other way.
It started with Slide 17, in fact, which showed that exit velocities on fly balls and grounders had gone up sharply but that line drives, mysteriously, had not -- they were being hit only as hard as they had been the year before. The conference presentation that immediately followed Nathan's, by Brian Mills, suggested that subtle changes in the strike zone could be driving the increase in home runs. (Mills, a brilliant academic, later adapted the presentation for an article at the Hardball Times.)
There's more. This year, fly ball exit velocities are up even more, from an average of 89.7 mph at this time last year to 91.5 mph this year. The average fly ball travels 10 feet farther this year, from 305 feet last year to 315 feet this year. Did MLB juice the ball even more, after everybody started whispering about it?
Probably not. Neither ground balls nor line drives have seen an increase, according to publicly reported Statcast data. In fact, line drives are being hit much less hard this year -- about 93 mph, down from almost 99 mph at this point last year. While it's hard to say conclusively, because the Statcast system does not successfully measure every batted ball and the system has in the past shown some measurement error, these trends suggests two things: 1) Batters are hitting more home runs because they're hitting fly balls harder; 2) but they're not hitting line drives (or even ground balls) harder. Taken together, these suggest that a change in approach, by hitters and/or pitchers, might be driving the home run spikes. They suggest that hitters are able to increase their hard-fly rate while perhaps sacrificing other hard-hit balls.
(This is not a totally satisfying hypothesis, but at this point none are.)
On Monday, though, we got the most convincing evidence against the juiced ball theory. The Ringer's Ben Lindbergh reviewed and reported the results of the league's "extensive testing" of its baseballs.
"The report is an 11-page document that summarizes the results of testing conducted in July 2016 and February 2017 by the Baseball Research Center at the University of Massachusetts Lowell, which has overseen MLB's ball testing since the late 1990s (separate from additional testing by baseball manufacturer Rawlings)," Lindbergh wrote.
"The report says that all of the baseballs were not only well within the limits of MLB's fairly broad manufacturing specifications, but also 'comparable in weight, circumference and COR to previous compliance data,' an assertion supported by plots of average values and 95 percent confidence intervals for each of the previous testing periods."
The league had previously cited these reports but never shared them. Now, finally, we could see that they existed and said what the league had claimed they said. Not only that, but last summer the league brought Nathan aboard to review the research.
"Quite frankly, I was disappointed at that result, because I was hoping I'd find something," Nathan told Lindbergh.
As a condition of getting the reports, Lindbergh had to agree not to release them; he was only able to describe, summarize and quote selectively from them. Major League Baseball has a "non-smoking gun," in Lindbergh's words, yet remains oddly secretive about it. It's a pretty good strategy if their goal is to ensure that there will continue to be conspiracy theories alleging sinister interventions by the league office.
There's a pretty good case that it's in the best interests of baseball to manipulate the ball to add or subtract offense. It's broadly agreed that low-offense eras are bad for baseball's business -- hence the conspiracist's easy belief that Major League Baseball would engineer more hitting. It might also be hypothesized that too many home runs make for a more static game, as pitchers are forced to nibble and resulting increases in walks and strikeouts create a sort of feedback loop. Furthermore, it's a popular, romantic notion that baseball stars can be compared across eras, and the more the game's offensive environment changes from one decade to the next, the more ambiguous and the less satisfying these comparisons are. The commissioner should consider tweaking the composition of the ball to counteract the other dominant forces of each era.
Now, there is also a case that the league should leave the ball mostly alone. As it is, the commissioner's office is mostly free from blame when offense goes up or down, but if it took an active role in changing the baseball it might be stuck "owning" every swing in the offensive environment. The imprecision of baseball construction -- there can be a lot of variation from batch to batch, and small variations can make a big difference -- might open the league up to all sorts of unintended consequences. As Lindbergh told me by email Wednesday, "As intensely as a small subset of analysts pays (and draws) attention to changes in the game, a rising home run rate isn't something most fans would fixate on unless you gave them a reason to. Tell them that the ball is different, and they might decide that they don't like things this way and blame MLB for tampering with a game that they love, especially since statistics and adherence to tradition are a big part of baseball's appeal."
It might also be something the league would have to collectively bargain. (Two labor lawyers I talked to were both able to argue that juicing the ball would and wouldn't be subject to collective bargaining.) But it's a certainty that the league would have to deal with unhappy players -- roughly half of them every year, depending on which way offense was going. Perhaps the league is best served asserting its non-scandalous right to change the baseball but leave it mostly untouched.
In which case it can still take the issue out of the shadows. Letting Lindbergh see the results of its studies was an obvious, positive first step. The next is to release these studies fully as a matter of routine business.
"Based on background conversations I've had with league officials, regularly releasing ball-testing results is something they've considered," Lindbergh told me. "If they start doing that, though, they'd have to keep doing it, because it would be suspicious if they stopped. And even if they haven't tampered with the baseball this time, they might decide to do so at some point."