K: A History of Baseball in Ten Pitches - Tyler Kepner

Each chapter in the book is devoted to a different pitch. Kepner will usually discuss the earliest recorded example of the pitch, the inventor of it, if you can determine that. The curveball, for example, has been credited to several different people, as different people claim to have thrown it at one time or the other, or learned it from this person or that. It's very cool to realize there are times where you can trace a lineage of people learning a pitch from the early 1900s up to now. Just a string of one player teaching another, who becomes a coach, who teaches other players, who teach others, and so on. Just like any craft.

Kepner interviewed a lot of players and coaches for the book, went through old game summaries and other books and writing on the topics. It feels like a book with a lot of research and affection put into it, but doesn't bog down in the details. He'll discuss how you grip different pitches, and the different ways different pitchers throw the same thing, differences in what they do with their wrists or finger placement, as well as what impact that has on the ball's movement.

Kepner doesn't try to pull everything together in some final chapter, but each chapter does discuss the shifting popularity of the pitches over time, and the reasons for it. The knuckleball is always a niche pitch. The sinker is declining in popularity (or sinking) because all hitters are trying to loft the ball now, so the pitch drops right into their swing plane. The slider and splitter were both extremely popular at one time, but they, along with the screwball, have fallen out of favor because they're believed to be too hard on the arm. Except Steve Carlton threw a damn slider for 4,000 innings and says his arm never hurt (while Bob Gibson admitted he sometimes took frickin' horse tranquilizers to deal with the pain his slider caused his elbow).

Maybe pitching is just something a person's arm isn't built to do that much. This does get brought up, although there are people who insist it's just because everyone is throwing the wrong way. Mike Marshall really seems to think he's the only smart man in all of baseball.

'Finley is indeed one of the few left-handers associated with the splitter, an oddity that makes it a little like the knuckleball, which is also thrown almost exclusively by right-handers. Because lefties are harder to find, they tend to get more chances to stick, and rarely must resort to a last-chance trick like the knuckler or splitter.'