Zack Littell on His Two Sliders

Zack Littell was stellar out of the Minnesota Twins bullpen in 2019. In his first big-league season as a full-time reliever, the 24-year-old right-hander went an unblemished 6-0 with a 2.68 ERA in 29 outings covering 37 innings. His slider was a big reason for his success. Make that his pair of sliders.

“They’re two different pitches,” Littell told me late in the campaign. “When I got moved to the pen and got rid of the curveball — a pitch I’d had my whole career — they said, ‘We’re going to go predominantly slider-fastball, and mix in a few changeups.’ I kind of got used to that, throwing a lot of sliders.”

That would be an understatement. The North Carolina native threw the pitch… er, the two pitches, a full 49.6% of the time last year. He threw his four-seam fastball 48.6% of the time.

Littell, who we first wrote about in 2016 when he was a 19-year-old unranked prospect in the Seattle Mariners system, originally developed a slider in 2017 after being traded to the New York Yankees. At the time, “it was more lateral than downward,” and while the righty called it a slider, it was “pretty much a big cutter.”

For the most part, that didn’t change until his demotion-triggered makeover last June. Littell had made a pair of appearances in late May, the second of which saw him shellacked by the Tampa Bay Rays. Much to his chagrin, Littell surrendered 10 hits and eight earned runs in 4.1 innings. After the game, he was optioned to Triple-A.

In his 2018 rookie season, Littell had thrown his cutter-ish slider 16.9% of the time, which was only slightly more often than he’d gone to his curveball (13.1%). Scrapping the latter and focusing on the former proved a panacea. Not only did he develop better feel for what is now his signature pitch, he discovered that he could “add a little depth, take a little bit of depth off, throw it harder, throw it softer.” Over a relatively short period of time, he morphed into somewhat of a master manipulator.

Soon after Littell was called back up to the big leagues, Twins pitching coach Wes Johnson pulled him over and said, “Hey, we like what you’re doing there; why don’t we go ahead and keep differentiating a cutter and a slider.”

Minnesota’s catchers weren’t part of that equation. They simply continued to put down fingers for a slider, and depending on what the situation called for, Littell would opt either for more depth or more cut.

The means of manipulation are pretty straightforward.

“The grips are exactly the same,” Littell explained. “It’s more wrist position. On the true slider, where it’s a little bigger and I get more downward action, I really focus on supinating. I wouldn’t say it’s just like when you’re throwing a curveball, but I’m kind of getting on the right side of the baseball and creating that corkscrew spin, which gives you depth.”

“Conversely, when you’re still getting backspin, but also sidespin, you’re going to have more of a true cutter. The force of gravity doesn’t work quite as hard on the baseball.”

Technology predictably played a part in Littell’s slider evolution — Rapsodo and Edgertronic units were usually close at hand — but so too were old-fashioned mental cues.

“For the [true] slider, I have to tell myself to make sure I get my hand out of my glove early and up close to my ear, almost like I’m short-arming as a catcher would,” said Littell. “Catchers are taught, ‘ball straight to the ear,’ and I have to think that way. All that does is make sure that my arm is out front. If I’m late at all, if my body is moving down the mound, my shoulder already opened up, my head having opened up… it’s very hard to get on top of the baseball when your arm is behind the rest of your body. Making sure I create that topspin is important.”

As real as that is, the action exists solely between his ears. Littell made it clear that no discernible differences can be seen on video. Each version of the pitch looks the same throughout his delivery, and out of his hand.

That wasn’t the case with his curveball.

“One of the reasons for getting rid of my curveball was not tunneling it well,” Littell told me. “It would pop up out of my hand, so it wasn’t playing for me. That’s why we decided to go just fastball-slider, and eventually fastball and multiple sliders.”

Don’t be surprised if “multiple” ends up meaning three. According to the former 11th-round draft pick, that idea was tossed around when his curveball was exiled to his back pocket.

“When we first sat down, the idea was to see if we could make it three different pitches,” recalled Littell. “Have a true, very small cutter. Have an in-between slider-cutter. Have a true slider, something a little bigger. They’d all range from the low-to-mid 80s and tunnel well off my fastball. That never really happened, but it still could. We’re not going to be forcing anything, but maybe next season I’ll have all three.”

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

Great article. Interesting to see what the three outputs are over the course of this year if he does manage to mix in that third pitch.