Major League Baseball has released a scientific study that was designed to examine “possible causes of the surge in home run rate in Major League Baseball in the past several years,” as its abstract puts it. The study itself is available at this link. Those interested in reading an independent breakdown should check out the assessment of the Baseball Prospectus team, which has covered this topic well for quite some time.
Per the report, the focus was on utilizing Statcast data and a variety of means of evaluating the physical properties of the game balls utilized in recent seasons. That follows years of increases in home runs — along with additional strikeouts and quite a few other changes in the game environment — that have led to accusations (increasingly supported by evidence and analysis) that some change to the game ball has occurred.
While the findings don’t suggest that there has been any change that increases the ball’s “launch conditions” — that is, the ball isn’t juiced — they do find that “aerodynamic properties of the baseballs have changed” in a manner that corresponds to the increase in batted-ball distance. In other words, balls are being struck in roughly the same manner, but are going further than previously.
That largely seems to confirm, then, that a recent change of some kind is the underlying cause of the homer boom — a major modification in the nature of the game that has caused changes with in-game tactics and drastically impacted player valuations. But the committee did not precisely identify the physical reason for the changes in flight characteristics, and in fact specifically found that the manufacturing process and materials weren’t the cause.
Interestingly, the study determined: “The yearly reduction in average drag, which accounts for the change in the home run rate, is small compared to the variation in drag among baseballs within a given year.” For that reason, perhaps, many of its suggested actions revolve around standardizing the factors that influence drag.
Certainly, readers will want to read through the entire report — or, at least, its essential findings. At this point, it’s not yet clear exactly how and when the league will pursue changes. But if there are systematic efforts to restore the baseball’s previous flight characteristics, that could portend yet more adjustments and changes to the marketplace, as it reacts to observed changes in game conditions and outcomes.