I had first talked to Bouton 25 years earlier, in 1992, when I was a teenager and had just read “Ball Four” for the first time. I was an aspiring sportswriter but also a frustrated high school pitcher — a warm-up guy. When I read his book, Bouton seemed like a friend. It was good to know there was someone like him out there.

“I don’t think any teenager feels comfortable in his group,” he told me then, when I mentioned how deeply I connected with the book. “You’re trying to figure out how the world works: ‘How do you get from here to there, who am I and how do I fit into things and what the hell am I going to do with my life? I don’t have any answers.’ And so to read a book by a guy who’s in the same situation, who’s 30 years old, they have to say to themselves, ‘Hey, it’s O.K. to be on the outside.’”

Bouton found his way to the inside through his success with the Yankees. He won 21 games in 1963 and 18 the next year, plus two more in the 1964 World Series. He threw so hard that his cap always fell off his head.

But success did not last, and by 1966 he was barely hanging on. He turned to the knuckleball, a pitch he learned as a young New York Giants fan. In 2015, he told me how he developed it:

“I learned the knuckleball when I was about 12 years old and there was a cereal box with a picture of Dutch Leonard on it,” Bouton said, referring to a Washington Senators All-Star from the 1940s. “It explained on the back of the box that the trick was not to throw it with your knuckles. The idea was that you really need to throw it with your fingertips, without any spin.”

It seemed like an impossible task, and it confounded Bouton. But, determined to master the pitch, he kept at it.