MLB’s Home Run Increase: Is the Baseball Juiced, or is Something Else Happening?

PITTSBURGH — If you haven’t heard the news, there’s something up with the baseball.

Both The Ringer and FiveThirtyEight have published stories in the last month with groundbreaking evidence that shows that since about the midpoint of the 2015 season, there have been small but impactful changes to the size, seam height and bounciness of the ball that’s used by Major League players. Those changes have come with a dramatic increase in home runs.

But not everyone is convinced. Pirates general manager Neal Huntington thinks that there are other factors at play.

“We believe there’s some underlying issues to this,” he said on Sunday. “We’ve become a showcase-based industry, where it’s about how hard can you throw, how far can you hit it? That’s what gets you recruited to colleges and what gets you signed professionally. The pitchability, the ability to develop a breaking ball, the ability to develop a changeup, the ability to get weak contact, those things are going by the wayside.

“I don’t have an answer why it spiked in August of 2015. But the lack of pitchabilty, the focus on velocity, the focus on hitting home runs, that speaks to some of why we’re seeing what we’re seeing. But it probably is a new normal. Guys are going to throw harder, they’re going to get injured more, and hitters are going to look to hit home runs.”

Count starting pitcher Gerrit Cole as one of those that remains unconvinced that the changes to the baseball have made a significant factor, despite the fact that he’s seen a career-high HR/FB rate this season. But he certainly agrees with Huntington that there’s been a change in the approach of many hitters and young hitters in particular.

“I’ve definitely seen a change in approach,” Cole said. “As a league, we started striking out a lot and guys were losing their jobs because they were striking out so much. But then the industry found out that there was value in production over average. Strikeouts became acceptable as long as you can slug. I definitely think there’s a different approach with launch angle. You see some of these guys coming up with uppercut swings. The three (Los Angeles) Dodgers guys come to mind. Kris Bryant comes to mind, the younger (Chicago) Cubs guys come to mind. I’m sure that’s a conscious approach.”

Countering an Earlier Trend

At the intersection of those two trends lies pitchers that rely on the two-seam fastball. If hitting for launch angle is today’s trend in Major League Baseball, the two-seamer was yesterday’s, as the Pirates and other teams used a combination of sinkerball pitchers and shifting defenses to have success in the early 2010s.

In fact, the two trends are probably related. As more and more pitcher began to employ the two-seam fastball as a primary offering, the need for an upper-cut type swing that could still drive those pitches became necessary.

“I don’t have awareness of any player on our club trying to develop a golf swing trying to hit the ball out of the ballpark,” manager Clint Hurdle said. “But you can gauge every player’s launch angle now and look at what it was a two years ago, look at what it was a year ago and look at what it was this year. There’s some that are changing within the years. … The numbers prove it.”

Ivan Nova is a pitcher that’s relied a lot on his two-seam fastball and an aggressive approach to throw a lot of early strikes and get ahead in the count. Recently, that approach may have led to some home runs as players have been sitting on his sinker. Of course, the point of the sinker is that usually, even if a hitter is ready for it, the ball is hit on the ground. The popularization of uppercut swings may be changing that.

Former Pirates relief pitcher Jared Hughes knows something about the sinker. It’s been his primary offering since he came into the league in 2011. He’s also seen changes in way it’s attacked, but he’s not sure how successful that approach will be long-term.

“If there’s a guy that’s outstanding at hitting sinkers and he’s proven he can hit mine, why would I not go up?” Hughes asked. “I have a four-seamer, too. I have decent velocity on the ball. Shoot, that’s what I did growing up, right? If I need to go back to it, I will. … There’s definitely some guys across the league that you know you have to go up to. Honestly, anyone, you can go up out of the zone to and try to get them to chase. Even as a sinkerball pitcher, that’s a part of my game. Has it become more a part of my game? I think so.”

Hurdle agrees with the notion that a change to a swing to make contact with balls lower in the zone will more than likely have consequences other places.

“Watch (the Home Run Derby) just for lifting a baseball and then watch the pitchers when they get into the (All-Star Game),” Hurdle said. “They played 10 innings and the score was 2-1. … It’s not that easy.”

Pirates pitching coach Ray Searage isn’t telling his pitchers to do anything differently. He still wants them to dominate the bottom of the strike zone first and foremost and then go upstairs when necessary. But the changed swing patterns do put an emphasis on execution. Now more than ever, mistakes can end up in the seats.

“We want them to own the bottom of the zone and then work their way up,” he said. “Own the bottom of the strike zone, know when you have to pitch up and then it just boils down to execution and hitting the four corners of the strike zone. We’re not concerning ourself with that other stuff.”


  • Why does this make me think of Pedro Alverez?

  • The mere fact that HR/FB increased sharply mid-season has me convinced it’s the ball. I’m completely on board with swing changes and increased velocity enhancing the effect over the last 2 years, but the effect is on the margins compared to the ball, which has been showing both an increase in exit velocity and an increase in average distance per exit velocity/launch angle pairing, suggesting the ball became – quite suddenly – both more elastic and more aerodynamic.

    Just at the time the Pirates were drafting low power, contact-oriented, hit-to-all-fields types, I might add. Almost makes you wonder if in 2 years the poster child for the 2015 draft will end up being neither Kramer nor Newman, but Casey Hughston.

  • Not only the ball and batting approach, but the San Diego Tribune says that the PED usage, despite the increased testing, is still quite rampant. Victor Conte (Balco), who is now ‘legitimate’, says that players and sellers are getting smarter and smarter at disguising it in their bodies. The financial gain still outweighs the risk of bieng caught.

    Chicks dig the long ball (and so do fans) so I think that lots of HRs are here to stay.

    • I agree, I think PED use is on the rise again. I’m still trying to figure out how Charlie Morton is now a 100mph starting pitcher in Houston along with the entire team (except altuve) looks like they could be a starting linebacker in the NFL

  • Baseball is a cat and mouse game between pitchers and hitters. I expect to see more traditional 4-seam fastball, overhand curve, changeup pitchers to be used to counteract the uppercut swings favored by many young hitters like Bryant, Berlinger, Judge, etc.

    In the meantime, hope you chicks dig the long ball!