One Complication for the Slicker-Ball Theory

The thing about the slick-baseball theory is it’s so easy to believe. To review, as quickly as possible: Pitchers believe the World Series baseball is different. Like, the actual baseball itself. They suspected it was kind of different earlier in the playoffs, but now they think it’s more different. It’s different by feeling more slick, more slippery. You can imagine how that could pose a problem. What are pitchers to do if they’re not accustomed to their instrument?

So the idea goes, it’s had a profound effect on sliders in particular. Anecdotally, you can get behind it, because we’ve seen some sliders get hit hard. But the other evidence is even more compelling. There’s the blindfold test. There are pictures. And, simply, there are the pitchers, speaking their minds. Experienced pitchers, who you’d think would know what a baseball feels like more than anyone. This is more than just one or two guys. Tom Verducci spoke to players and coaches from both the Astros and the Dodgers. Why would you doubt what the pitchers have to say? Why would they just make this up?

I don’t think they are making it up. I think pitchers do have a certain sense for things. I’d just like to present a graph.

This theory isn’t universally believed. No theory is universally believed. Major League Baseball has already come out and said there’s no difference in the balls, aside from the different postseason stamp. But that shouldn’t do anything. Of course, MLB has every reason to try to deny something like this, so, perhaps more believably, there’s Rich Hill.

The Dodgers’ Rich Hill, who will oppose Verlander in Game 6 and throws more curveballs than sliders, said he thought the balls felt the same.

“I think they’ve been extremely consistent in the World Series, and also in the playoff games as well,” Hill said, adding that he had not seen any variation in the seams of the ball, or the size. “I think it just has to do with the conditions. If it’s colder, it’s going to be slicker. If it’s a little warmer out or humid, I think you’re going to have a little bit more moisture to the baseballs.”

It’s possible that Hill is outnumbered. Indeed, it seems probable that Hill is outnumbered. We can’t know the opinions of the pitchers who haven’t been asked, or who haven’t shared their thoughts, unsolicited. Hill’s a breaking-ball guy. Seems fastidious. You’d suppose he’d know if something was up, but then the exact same argument goes for Justin Verlander, who has detected something weird. Look, I don’t know. It’s just that the slick-ball theory isn’t unopposed.

But we can look at some other numbers. We can do a little bit of indirect research. Pitchers will tell you what they think. There are two ways for them to share their thoughts. There is, of course, the spoken way. Providing background, or going on record. Several pitchers have opted for the spoken way. That’s how Verducci composed his whole article. But then there’s also on-field strategy. When the games are played, and especially when they’re as important as the World Series is, players won’t lie to you. They’ll perform in the way they think will maximize their chances of winning. So this actually makes things really easy. There’s a theory that the baseball is different, affecting sliders in particular. If sliders are worse, it stands to reason pitchers would throw them less often. Have pitchers changed how they’re pitching?

I grabbed data from Brooks Baseball, using the classifications of pitches as hard, breaking, or offspeed. I looked at the World Series, I looked at the first two rounds of the playoffs, and I looked at the final month of the regular season. And for all these splits, I examined the 16 pitchers who have thrown at least 40 pitches in the World Series so far. On the low end, there are Tony Cingrani and Ken Giles, with 41 pitches. At the upper end, there’s Clayton Kershaw, with 177. I calculated the weighted-average pitch frequencies, for all three time periods. Here’s what came out.

There’s just — there’s not really much of anything there. The rate of hard pitches has gone from 63% to 62% to 64%. The rate of breaking balls in the World Series is down three percentage points from the first two rounds, but it’s an exact match for the rate of breaking balls in the final stretch of the regular season. There’s not much going on with offspeed pitches. Based on their words, some of the pitchers have indicated that their arsenals have been weakened. Based on how pitchers have pitched, it doesn’t look like they’ve lost faith in their breaking stuff.

Now, it’s worth remembering that every pitcher is different, and so every pitcher might be differently sensitive. Brad Peacock, for example, broke out this year in large part because of his slider, but in the World Series he’s mostly left his slider on the shelf. On the other hand, Kershaw has thrown a higher rate of breaking balls in his two starts. As mediocre as his slider seemed in Game 5, it was great in Game 1. Game 1 of the World Series involved World Series baseballs.

Another point is that, well, perhaps it’s not that breaking balls are most affected. Maybe all pitches are kind of equally affected. In which case, you wouldn’t see changes in frequencies, because, what would be the purpose? Might as well pitch like normal and hope for the best.

There’s one last possibility, as I see it: Maybe pitchers are stubborn. Maybe they’ve believed their breaking balls are worse, but they’ve forced them anyway, pitching against their own best interests. I’m disinclined to believe this explanation, but I should put it out there, in any case. Who knows? No one wants to have to pitch without their breaking balls. You try to make them happen. You try, and you cross your fingers.

I don’t think it’s all necessarily connected to how World Series offense has been up. Pitchers might complain no matter what. But the theory’s more resonant with the balls we’ve all seen flying out of the yard. To which I’d respond, these are the two best offensive teams in the playoffs. The Astros are one of the better offensive teams in history. We know that the Crawford Boxes in Minute Maid Park allow for some silly home runs. And the game-time temperature for Game 1 in Los Angeles was 103 degrees. The game-time temperature for Game 2 was 93. Balls carry when it’s hot. In the World Series, compared to the first two rounds, the Dodger lineup’s strikeout rate is slightly up, and its walk rate is down. The Astros lineup’s strikeout rate is the same, and its walk rate is down. Turn a few weak home runs into doubles or outs and suddenly this looks like a regular series.

There’s nothing I think is strongly conclusive either way. I can’t in good conscience dismiss what pitchers are saying about how the ball feels, but then, they’re not all saying it. The hitting in the World Series has been mostly normal, overall, and pitchers, as a group, haven’t meaningfully altered their pitch frequencies. It’s complicated, and presently unknowable, and this is more of a bad thing for baseball, given there were already other concerns about how the ball has been playing. Baseball could stand to be a lot more transparent. But as for the World Series ball, specifically: I just don’t know. Nothing’s quite as certain as it seems.

We hoped you liked reading One Complication for the Slicker-Ball Theory by Jeff Sullivan!

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Jeff made Lookout Landing a thing, but he does not still write there about the Mariners. He does write here, sometimes about the Mariners, but usually not.

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Mike D
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Gaylord Perry wouldn’t mind the World Series ball.