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With All the Questions About the Home Run Spike … Maybe the Ball is Juiced After All

MLB News and Rumors

In 2016, Major Leauge Baseball players hit a combined 5610 home runs – the second most collective league homers in a single season ever – and they haven’t slowed down this season. Indeed, the 2,395 home runs already hit this year are on pace to shatter the record.

And while that’s crazy in its own right, of course, it’s even crazier to think that last (and perhaps this) year’s total beats the MLB seasons of 1999, 2001, 2004, 2006, 2003, 1998, and 2002 (an era we know was riddled with performance enhancing drugs).

Many people around the game have tried to explain the spike in home runs (that really began at the end of the 2015 season, if I recall correctly), but most wind up with something along the lines of “it’s a confluence of events,” largely tied to changing batter and pitcher behavior.


And while that’s probably mostly true, sometimes you want to land on something just a little bit more concrete. Enter: The Ringer.

At the Ringer, Ben Lindbergh explains that MLB’s recent homer binge is at least partly due to the fact that “The Juiced Ball is Back.” Back? What do you mean back? When did it come back and when was it here before? Patience, my friend. I will explain what I can, and then, of course, you should check out the full article and explanation for yourself.

Here are four of the initial pieces of evidence, according to Lindbergh:

  1. In short, while the myriad other explanations (differences in the weather, pitch velocity, the fly ball revolution, changes to the strike zone, etc.) could and probably did have an effect on the number of homers hit, the sudden and dramatic spike points to something slightly more acute. In other words, if it were a confluence of natural changes, shouldn’t the rise have been more gradual? The answer is likely, yes. Yes it should.


  3. In addition, Lindbergh points out that past changes to the baseball’s composition have “produced dramatic rises and reductions before.” And that’s not just in the Major Leagues (where it has happened before). Japan, the NCAA, and the Mexican League have apparently all dealt with production changes due to new types of baseballs. So, at the highest level, this has more credibility than a conspiracy theory (in case that’s where you were at, for some reason).
  4. Moreover, while MLB experienced a spike around the time a new ball was introduced back in the middle of 2015, the Minors didn’t follow the same trend. Which is obviously quite suspect, considering that they used a different ball (made in China) than the new ones used at the MLB level (made in Costa Rica).
  5. And finally, the homers have been distributed disproportionately, “flattening the distance between hitters on the home run leaderboard rather than inflating any individual totals to record highs.” In other words, less powerful hitters have derived bigger benefits (guys with warning track power stand more to gain with a few extra feet on a fly ball than guys who already hit it well out of the park).

Obviously, those are some really convincing arguments, but here’s the biggest problem: MLB officials (including the Commissioner himself) have insisted that the ball has NOT changed. And, indeed, two separate studies concluded the same thing.


Despite those conflicting/discouraging reports and studies, Lindbergh continued to search for a way the ball had impacted the rise of home runs, and, what do you know, he found one.

Late last year, Lindbergh’s co-author, Mitchel Lichtman, took it upon himself to begin an independent ball-testing study (you can read about how they went about that in the article) and what he found was pretty convincing. In short, thanks to a combination of a higher COR rate (basically, it’s bounciness) and dynamic stiffness as well as a lower seam height, circumference, and weight, the newer baseballs could/should have theoretically gained 1.43 MPH in exit velocity! That’s huge, and can add several feet to a batted ball!

Obviously, as with most studies, there are plenty of caveats, issues, data problems, external variables, and other concerns, but still … wow. It seems to me, and this is a fairly technical read once you get all the way down, that the COR rate has the biggest affect, but is pretty confusing to everyone overall. After all, according to their work, a .012 increase in COR could account for the entire home run spike in the second half of 2015-2017, despite the fact that MLB allows for a COR range that is .064 wide.

The study (and article) goes on from there (it’s deep!), but for the sake of sparing you two lengthy reads in a row, I’ll just nudge you in their direction. It’s a confusing situation, and one of which I suspect we’ll one day get to the bottom. For now, know that there may be some reason to believe the baseball has changed in a way that creates more home runs … but MLB doesn’t believe that’s the case. Mysterious times, indeed.



Michael Cerami

Michael Cerami is a Writer at Bleacher Nation, and you can find him on Twitter at @Michael_Cerami.