We’re in the midst of seeing the largest year-over-year jump in sliders in a decade. So far in 2019, they’ve accounted for 17.9% of all pitches thrown. Last year it was 16.9%, and before that it went up or down by less than a percentage point between any two seasons. It may not seem like a lot, but the sheer amount of pitches leaguewide each year—upward of 700,000—makes even the smallest percentage increase significant. Sliders are up by the thousands.
Other offerings have been down at the expense of all these sliders. Collectively, every fastball type is down nearly 2 percent as hitters have been trained to crush heat. Specifically, the slide piece is supplanting the two-seamer. This makes sense if we stop to think about it…or if we read this piece on swinging strikes per pitch type by Alex Chamberlain. Two-seamers get the least amount of whiffs. As far as common pitches go, sliders get the most. The way the ball is juiced right now makes it hard to argue against pitchers optimizing for the swing and miss; any contact can jack up a pitcher’s stat line and put a game in jeopardy more than ever. But for the Rays—baseball’s best pitching staff, with 16.2 fWAR—this movement doesn’t seem to matter.
|Pitch Type||Rays Usage%||League Rank|
The staff’s pitch mix is interesting. They’re throwing the fifth-least four-seamers in the league and are right in the middle with cutters. But here’s where it gets weird: The Rays are throwing the seventh-most two-seamers and the fifth-fewest sliders, and are somehow still generating the second-most strikeouts in the major leagues.
Seven of the 13.5 pitchers on the active roster (hi, Brendan McKay) throw a two-seamer as one of their primary offerings. Each of those seven throws it 20% or more, which is at least 4 percent more than league average. Five of those guys come on in relief: Ryan Yarbrough, Diego Castillo, Adam Kolarek, Chaz Roe, and Andrew Kittredge. They offer a different look at an unpredictable moment in a game where the previous pitcher may not have thrown a two-seamer at all. The other two sinker-ballers are traditional starters in Charlie Morton and Yonny Chirinos, who might set up someone like Hunter Wood or Emilio Pagan who can and do lean on sliders. Let’s look at how it all breaks down:
|Pitcher||FT SwStr%||FT Called%||FT CSW|
So we get a glimpse here of how the Rays staff uses its two-seamers. Castillo and Kolarek are better than average at getting whiffs with the pitch. Roe excels at using it to get called strikes. Yarbrough does both really well, which adds another layer for the opposition to unpack as he comes in as the bulk reliever after an opener. The two traditional starters are each hovering around average. As a group, everyone but Castillo and Chirinos has a CSW with the pitch that’s better than league average.
Beyond how these pitchers use their two-seamers to get strikes, there’s also an added layer of deception in where they locate it. We could reasonably expect the natural movement of the pitch for Morton and Kolarek, as righties, to run to the third base side. Except it doesn’t; instead, it busts to the first base side and creates a totally flipped look for hitters. The same goes for Roe, but as a lefty the pitch runs to the third base side when we’d figure it would wiggle toward the first base side. Even if a hitter knows a pitcher’s tendencies, it can still be a tall task to reorganize their brain from what they’re used to only for an at-bat or three against something different.
In addition to using the two-seamer more than most of baseball, a handful of Rays pitchers are also doing something else unique. They’re throwing splitters. Remember up top, when I mentioned that sliders are the most common pitch that get the most whiffs? The only offering that earns more whiffs is the splitter. The thing is, though, barely anyone throws it. Just 29 pitchers have thrown at least 50 so far this year. Meanwhile, Chirinos (377), Oliver Drake (265), and Ryne Stanek (187) have chucked it a ton, to the point where the pitch accounts for at least 21% of each of their arsenals. They’re the reason that, as a team, the Rays are throwing more splitters than any other club by nearly 2.5 percent.
By and large, they’re using these pitches to get whiffs or called strikes early in at-bats, then, as a staff, using the kitchen sink to get the third strike. This is the kind of strategy that the Rays have had to historically seek out in order to even sniff success. How long might this one work? Two-seamers can be timed up by hitters because they move side-to-side and can be easier to track. They also don’t necessarily work well in conjunction with other pitches. But as far as the splitters go, those are just tough to crack. Hitters simply may not have seen them enough before now to have the reps that would allow them to start barreling them with more frequency in the immediate future.
Regardless of how well this approach works out for the Rays over the rest of the season and beyond, there might be another lesson here; one we might already have learned but for which we need reminding. There are opportunities in baseball to reach success by zigging when everyone else is zagging.
(Photo by Cliff Welch/Icon Sportswire)
Whoa. Maybe they did the same research that Alex Chamberlain did recently: https://fantasy.fangraphs.com/pitch-type-xwoba-on-contact-xwobacon/
“Throw a splitter, folks.”