Larry Andersen, Durbin Feltman, and Trevor May on Crafting Their Sliders

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.

In this installment of the series, we’ll hear from three pitchers — Larry Andersen, Durbin Feltman, and Trevor May— on how they learned and developed their sliders.


Larry Andersen, Philadelphia Phillies (broadcaster)

“I was a sophomore in high school, and we had a senior pitcher named Don Beckwith who had a slider. At the time, I just had a fastball and a curveball. He showed me his grip and I was like, ‘Let me try this.’ From there I implemented it into my repertoire. It was a pitch I picked up right away. It felt comfortable. It’s almost like holding a fastball off-center a little bit.

“Of course, then there was the pressure on my fingertips and how far back I held it in my hand. That type of thing. I played with those over the years to the point where I felt I had three different pitches with essentially the same grip Don Beckwith showed me in high school.

Larry Andersen’s regular slider grip.

“I held my fingertips on the seams the same way on all of them. It was just a matter of spreading my fingertips, keeping them together, or choking it back in my hand a little more. I toyed with those over the years and while I don’t think you ever perfect anything, I got pretty good with it.

Larry Andersen’s cutter-slider grip.

“The one I would cut was basically an off-center four-seamer. I would spread my forefinger and middle finger apart a little bit, like a fastball, but I would still be on the side of the ball. With my regular slider, I would keep my fingers together and try to keep that same pressure; I wouldn’t twist my wrist, but rather just pull down on the ball. I’d get a little downward tilt with that one. And then if I wanted a bigger break, and more downward break, I would get it back in my hand a little more; I’d choke it a little more. That one I probably did help a little bit. To get it slower, with that break, you almost have to help it with a little twist of the wrist.

Larry Andersen’s bigger-slower slider grip.

“You do manipulate [a slider] a little bit, but I still say — this is when I’m showing it or teaching it — ‘Don’t make it break; let it break.’ Too many times, if a guy want a little bigger break on his slider, he feels like he has to twist his hand, twist his wrist. That tends to hurt you, because you end up getting around the ball, getting under it more, versus just letting your grip dictate where it’s going to come out.

“For me, the finger pressure was on the outside of my index finger and the inside of my middle finger. They kind of worked together. Basically, I wanted it coming off the seam, just on the fingertips. Guys with curveballs get the grip down the seam — I think you really help it a lot more with the curveball — whereas with the slider… I felt like if I get down the seam, get my finger down the seam too much, then I’m going to end up wanting to throw it more like a curveball.”

Durbin Feltman, Boston Red Sox (prospect)

“My senior year of high school is when I started pitching. I’d been a catcher my whole life, and hadn’t really pitched at all. At first I had a curveball, a 12-6 true curveball. But I’d noticed that everything else I threw cut. This was even when I was playing dodge ball as a kid. I’d throw a dodge ball and it would just take off on me.

“When I got to college [Texas Christian University], my pitching coach, Kirk Saarloos, wanted to see if I could throw a power slider instead of that curveball. He wanted something harder and not as loopy, so we worked on it in a few bullpens, playing around with a few grips. Then I just started throwing it like a fastball, letting the grip do its work. That’s how it developed.

“I used both a curveball and a slider my freshman year, then they kind of morphed into one pitch. It’s kind of a slider, but some people call it a curveball. I guess I don’t know what to call it. It’s kind of a slider-curveball type deal — it has the velocity of a slider, but the depth of a curveball — so I just call it my breaking ball.

“I throw it with a slider grip, but with my arm angle — I’m so over the top — it’s hard for me to throw a true slider, a side-to-side slider. My arm action causes it to break more vertical, up and down. Tunneling it off of my fastball, with the depth it gets, I can get swings and misses.

“When I throw my slider, I think fastball. If I think curveball, I wrap it and it doesn’t move how I want it to. So I just think fastball, fastball, fastball, and then right at the end I let the grip take it. That moves my wrist a little bit, too. That said, I do try to keep my wrist stiff, but at the end my hand kind of naturally gets around it. In a way I kind of throw it how you’d throw a cutter.”

Trevor May, Minnesota Twins

“I’ve had a slider since I came to the big leagues, but it had basically been a fourth pitch. It was high-80s, around 86-88, and more of a wrinkle than anything. It wasn’t really a cutter, because it had more depth. It was just a small little… I never threw anything that had much horizontal movement. It just had a little vertical movement, and it wasn’t my curveball.

Trevor May’s slider grip.

“This year I was messing with grips and switched up the grip a little from my spiked curveball. I grabbed it similarly to my curveball — but I un-spiked it — and started throwing some that way. I was told by some of our analytics guys that the velo was around 85 and it was moving almost as much as a curveball. That raised a little bit of excitement about it.

Trevor May’s slider grip.

“There was a transition period where… basically, it’s a good hard curveball and I just didn’t have a feel for it. I didn’t really have a feel for a breaking ball at all, maybe in May going into June. Then the slider started feeling better, so I threw it more. I’d been getting hurt on the curveball; I threw that less. That’s where I am now. I technically still spike my curveball, but I haven’t thrown one in about a month. It’s more or less in the storage shed.

“Along with not spiking [my slider], I’m a little more on the side of the ball and it has more bullet spin. It’s really in between a curveball and a slider. It’s not 12-6 like the other one was, but it’s not a true slider, either. True sliders have a little more two-plane movement, while mine has more depth than horizontal. But we do consider it a slider, mostly because it’s not my curveball — those things are semantics usually, based on the pitcher. That said, it does compare to other sliders. It’s in the slider category.”


The 2018 installments of this series can be found here.

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.

1 Comment
Newest Most Voted
Inline Feedbacks
View all comments
4 years ago

Don Beckwith is Very smart, also a very strong senior pitcher. We love him.