Photo credit: Tony Gutierrez/AP

No matter how much MLB and worthy physicists deny it, and no matter how sincere they are, the balls used in major-league games are, it says here, juiced one way or another. It could be that central baseball, worried that declining levels of offense would bore fans, hatched a fiendish conspiracy; it could be that some change in the manufacture of the ball, so insignificant as to be undetectable, is to blame; either way, the ball is juiced.

Home runs per game have reached 1.24 this year. That’s an all-time high, and up 44% from just three years ago. Weather, random chance, and the Statcast-aided popularity of the idea that it’s good not to beat the ball into the ground may all have contributed, but such a widespread and rapid change demands a global explanation, and the only one on offer here involves something going on with the ball.

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One of the interesting things about this latest home-run binge is that it’s not showing up at the top of the batting leaderboards, where league-leading totals have been and continue to be historically normal; this isn’t the late 1990s, where every other decent left fielder could crack 50 cuadrangulars. Instead, the history is being made up on the other side of the ledger, where the pitchers with the flattest offerings are putting up scarcely believable numbers as 10-homer men become 15-homer men and 15-homer men become 20-homer men.

Consider this: Coming into this year, in all of baseball history, only four pitchers with enough innings to qualify for the ERA title had ever had a season where they allowed two home runs per nine innings. This year, seven are doing so. Even granting that it’s early and that a selection effect will take hold here soon—pitchers who give up home runs that often generally don’t stay in the rotation long enough to qualify for the ERA title—it’s an astonishing thing, especially since these aren’t all replacement-level jamokes. Mike Fiers is a perfectly adequate starter for a historically good Houston Astros team; John Lackey, Jordan Zimmermann, and Masahiro Tanaka, who’s given up 15 home runs in 42.2 innings since the beginning of May, are all nominal or actual stars. The king of the shelling and the perfect example of what’s going on, though, has to be our old friend Bronson Arroyo.

Arroyo, currently 79 years old and pitching, for unknown reasons, for the Cincinnati Reds, is allowing 2.91 home runs per nine, a third again as high as the 2.20 with which José Lima set the current major-league record in 2000. This is the product of a lot of things—the juiced ball, his nonexistent velocity and movement, the gopher tendencies that allowed a sprier Arroyo to give up more than two per nine in 2011, and so on—though not, interestingly, bad location. (Brooks Baseball tracks grooved pitches, and he’s not really laying them in any more than he ever has.)

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The all-time record for home runs allowed in a season is an awe-inspiring 50, set by Bert Blyleven in 1986. (He gave up 1.6 home runs per nine.) What mainly stands between Arroyo and this record (he’s on pace to give up 56) is the fact that he is elderly and terrible and cannot possibly stay in the Reds’ rotation; then again, it’s June and none of that has stopped him thus far. Whether anyone else can challenge 50 homers is unclear. Lackey and Tanaka are on pace to allow 48 and 47 home runs, respectively, but there seems to be something badly wrong with them, and it’s difficult to imagine them staying both this bad and in the rotation all year long; Zimmermann and Ricky Nolasco are just plain lousy, but on pace for 44 and 45 home runs allowed, meaning they’d have to get even worse to go for it; Fiers and Jesse Chavez are journeymen who probably won’t be given the rope it would take to crack 50.

There’s a real contrast between these pitchers and Blyleven, whose record was the product of a different era. The year he gave up 50, he was a strong no. 3 starter, who threw 271 innings with a 107 ERA+. His home runs weren’t a function of conditions or his shittiness so much as they were functions of his durability and commitment to throwing strikes, a variation on the idea that you have to be a damn good pitcher to lose 20 games. Entertaining as it may be at times, a league in which a pitcher can approach his record despite being terrible has an issue. If there wasn’t a conspiracy to start this, there ought to be one to fix it.