Pitchers learn and develop different pitches, and they do so at varying stages of their lives. It might be a curveball in high school, a cutter in college, or a changeup in A-ball. Sometimes the addition or refinement is a natural progression — graduating from Pitching 101 to advanced course work — and often it’s a matter of necessity. In order to get hitters out as the quality of competition improves, a pitcher needs to optimize his repertoire.
Ron Darling, Former All-Star
“When I first started throwing a split, I was one of those pitchers who could never develop a changeup. I was in the minor leagues with Al Jackson, who was a crafty left-hander in his day, and he taught me a screwball. He used to throw one. I got very adept at it, but it made my arm hurt. I had to develop a change-of-pace pitch that didn’t hurt my elbow, and that’s how the split-finger came to be.
“It was an era where the pitch was popular. Roger Craig taught it to a lot of pitchers, but it was a split-finger fastball for those guys. For me it was more of a forkball. It was something soft that I could combine with my fastball and hard curveball.
“The big difference between a split and forkball is velocity. If you throw 95 mph and throw a true split, it’s probably 88-89. The forkball I threw was around 80 mph. It was more of a changeup speed, and with a bigger break. I was primarily using it to have something soft, to get the hitter on that see-saw effect.
“I taught it to myself. What happened is that I couldn’t throw a changeup, so I started tinkering with different grips. I have big hands, so it was easy for me to grip the ball in my fingers. When I would sit on the bench — this is when I wasn’t pitching — I’d hold the ball in my fingers the entire game, to kind of spread out my ligaments. I was able to start gripping it wider and wider, which gave it more break.
“With the split, if you’re going with the seams — two-seam action — you would split your fingers on each side of those two seams. A forkball would be all the way down around the epicenter of the baseball. It’s deeper in your hand, which is one of the reasons you can’t throw it with a lot of velocity.”
Jack Morris, Hall of Famer
“I was throwing a side in Oakland during the 1982 season. Milt Wilcox and I used to always watch each other throwing our bullpen sessions, and I’d been struggling with my slider. It was flat — I wasn’t getting depth to it — and he asked me, ‘Have you ever thrown a forkball?’ I said, ‘What’s a forkball?’ I didn’t even know what it was. He said, ‘That’s what Bruce Sutter throws.’ I said, ‘Well, how do you throw it?
“He showed me how Sutter threw his, how he pushed his finger up through the ball and pulled his fingers around the outside of the ball. I tried about five or six, and nothing happened. I got a little frustrated and thought, ‘Well, that’s a waste of time.’ Then Milt said, ‘Put your thumb on the side; see if you can get your thumb out of the way and really pull your fingers. Make sure your hand is out front of your body when you release it.’ I threw about four more, and again nothing happened. Then I threw a fifth one and the bottom fell out. It just exploded. I started smiling, as though I’d just robbed a candy store. Two starts after that bullpen session, I was throwing it in a game.
“A forkball actually comes out of your hand with the rotation of a curveball. Because of the pressure on your fingers, there’s no way you’re going to have the same velocity you do with your fastball, therefore it’s kind of like an offspeed curveball. Once I learned how to keep it down, and literally bounce it at times, a hitter couldn’t sit on both. He couldn’t sit on a fastball and a forkball. It’s a devastating pitch.”
Tyler Thornburg, Red Sox
“I used to hit in college. One day a guy kept throwing this four-seam changeup, and I just couldn’t pick it up. It was really deceptive. I didn’t have a good changeup at the time, so I decided that’s what I wanted. I decided to try to make it spin just like my four-seam fastball.
“Like a lot of guys, I’d been gripping my changeup two-seam, trying to get movement on the ball. I was pronating, trying to have it be more of a fade pitch, rather than trying to be deceptive. Once I started spinning it, it became a good pitch for me. Coming up through the minor leagues… they do all those little grades, and I’d get best changeup in my league.
“To take velocity off, I try to miss as much ball as possible, as weird as that sounds. I try to pull straight down and spin it as much as possible without accelerating forward. And it’s a feel pitch. When I was a starter it was easier to throw, because I was throwing it often, rather than once or twice a game.”
David Laurila grew up in Michigan's Upper Peninsula and now writes about baseball from his home in Cambridge, Mass. He authored the Prospectus Q&A series at Baseball Prospectus from December 2006-May 2011 before being claimed off waivers by FanGraphs. He can be followed on Twitter @DavidLaurilaQA.