I saw this image from a Driveline Twitter account a while back, and it became my inspiration for this article.
There’s a narrative that sinkers aren’t as effective (or, effective at all) against opposite-handed hitters. They have a larger platoon split. I shouldn’t say, “there’s a narrative,” because I don’t want you to think the statement is false. It’s not. Sinkers absolutely perform better against same-handed hitters.
Sinkers are horizontal pitches, as opposed to four-seam fastballs, which are more vertically oriented. Against same-handed hitters, the arm side movement runs in on hitters’ hands, jamming their bats and inducing weak contact – often in the form of ground balls. Against opposite-handed hitters, that horizontal break doesn’t have as much room to operate, if you will. Picture a right-handed pitcher against a left-handed hitter. The pitcher throws his patented sinker to the lefty. The pitch leaves the hand, initially looking like it will land on the inner half. As the ball moves through its flight, it moves to the pitcher’s arm side, and in the middle quadrant of the zone. It’s Barrel City for the hitter. Now think about a sinker that starts middle, and eventually lands on the outer half to a lefty. Although a better outcome than throwing one middle, this sinker still doesn’t use its movement to its advantage. It’s not jamming hitters, and unless super well located on the edge of the strike zone, it is very hittable. So, should sinkers only be thrown to same-handed hitters, especially if there is a four-seam fastball in your arsenal?
A large part of this anecdotal consensus about opposite-handed sinkers is due to their pitch movement, as I outlined above. However, it’s not fair to count each sinker as the same. Each sinker is different, its own unique flower, if you will. Using blanket statements to describe the efficacy of any individual pitch type is short-sighted, so I decided to quantify different types of sinkers to see if the overarching notion reigns true. Below are each qualified right-handed pitcher’s average sinker since 2020 on a movement plot, colored by velocity (red is faster).
(Patting myself on the back for coding this pretty graph) Baseball Savant just made short-form pitch movement data available, so you bet your sweet kumquats I was all over that for this project.
To be definitive in my analysis, I first limited my research to vertical release points above 4.5 feet, to control for sidearm/submariners who skew movement data. Next, I calculated the median horizontal and vertical movement of sinkers, as well as the standard deviation of each. Finally, I added and subtracted half a standard deviation from each median value to get more definitive sinker shapes. In other words, I eliminated the sinkers that were close to crossing into another quadrant. There are three quadrants on the plot from which there’s enough data to make some strong takeaways: top left, bottom left, and bottom right. Now that we have our dataset, let’s dive in.
Drop and Run Sinkers
Let’s start with the most sinker-y sinkers there are. I’m describing this subset of sinkers sitting in the bottom right quadrant of our beautiful image from above as “drop and run” sinkers. How does this subset of sinkers play to same-handed and opposite-handed hitters?
It’s hard to tell from the clip, but this pitch came in at -1 inches of induced vertical break, an exemplary mark for a non-submariner/sidearmer. Overall, the average launch angle on Stroman’s sinker in 2022 moved from +12° against righties to -12° against lefties. Stroman’s outlier sinker shape has made him a platoon-neutral pitcher throughout his career. Here’s a fun nugget that further drives home the point I’m trying to make: Since 2020, there have been 67 pitchers who’ve thrown at least 100 opposite-handed sinkers that resulted in a batted ball. Stroman ranks 9th on that leaderboard in ground ball rate, behind pitchers who either use their physical capabilities to create awkward attack angles (Logan Webb, Richard Bleier, Clay Holmes, Josh Fleming, Aaron Bummer), throw a dropping sinker (Brad Keller, Jon Lester), or are Framber Valdez (alien, outlier, etc.). When it comes to release point and arm slot, Stroman is probably the most pedestrian member of this group. Even Keller throws a tick and a half faster than Stroman, who sits 90-91. Other pitchers who throw dropping sinkers include Graham Ashcraft, Camilo Doval, and Lance Lynn. In 2022, all three of these pitchers’ sinkers posted higher ground ball rates against lefties than righties.
There you have it. There is a subset of sinkers that perform as well, if not better, against opposite-handed hitters. Stroman’s excellence against left-handed hitters is a testament to his weirdness. He doesn’t throw super hard, or release the ball from a super weird angle. I am hesitant to proclaim success on this analysis for these exact reasons, though. My study left out two extremely important factors of sinker success: velocity and release point/arm angle. The top of the leaderboard from the above paragraph included Clay Holmes‘ 97 MPH sinker. The pitch has lots of success against opposite-handed hitters despite it being a traditional drop-and-run sinker because – breaking news – it helps to throw the ball hard. Moreover, it helps to have a super weird release point. Sinkers work great at the bottom of the zone, and higher release points create steep angles that are difficult for hitters to pick up when throwing a pitch with downward movement. I left these factors out of my analysis, but they should be considered when understanding sinker efficacy or inefficacy. Still, we have evidence now that a pitcher doesn’t necessarily need to eliminate his sinker when facing an opposite-handed hitter. I’ll leave you with some notes on pitchers who are throwing dropping sinkers this season. Seth Martinez has a dropper, but he hasn’t thrown his sinker to a lefty yet, opting instead for his four-seam fastball. It might be a good choice to incorporate the sinker to lefties, given his career .362 wOBA against lefties, compared to .251 against righties. Jake Woodford has upped his sinker usage against lefties from 26% to 41%. Clarke Schmidt has also stopped throwing his four-seamer to lefties, in favor of the sinker and his new cutter. A lot has been made of his struggles against lefties, but I think the answer has been in front of Schmidt all along.
The graphic was made by Kurt Wasemiller (@KUwasemiller)