Every baseball off-season has a topic du jour among baseball analysts. We’ve seen pulled flyballs, high line drives, spin rate, and others have their moment in the sun. MLB’s institution of the Hawk-Eye platform in place of Trackman for the 2020 season has given us the latest topic- spin mirroring for pitchers, and generally the way spin works for pitchers among different pitches. Let’s talk about that today, and which Cardinals best spin certain pitch sequences.
First, we should explain what we’re talking about. Think of the face of the ball as it exits the pitcher’s hand like the face of a clock. This Statcast image does a good job of illustrating the concept:
Generally but far from universally, most fastballs come out of the pitcher’s hand in the 10 to 2:00 range, at the top of the clock face. That includes sinkers, cutters, and four-seamers. Sliders and curveballs, however, usually come out of the hand at the bottom of the clock, in the 4 to 8 range.
You can go to this site and play around with how it looks if you adjust the tilt (the clock face/time). If you really want to do extra credit, visit that site and enter 12:00, and then enter 6:00, or any other pair that’s six hours apart. What you’ll see is that the seams look remarkably similar, but are spinning in the exact opposite direction. When two pitches do that, it’s called “spin mirroring.” When pitches are perfectly mirrored (exactly 180 degrees apart, or 6 hours on the clock face), it becomes more difficult for a hitter to identify the pitch and its direction.
Mike Petriello had a great breakdown of the concept mostly as it pertains to Shane Bieber, but he also includes several other examples of this and other concepts, like Lance Lynn and Kyle Hendricks. Eno Sarris also covered the spin mirroring concept for The Athletic. In the Sarris piece, he notes that the impact of spin mirroring is mostly muted... except on the extremes. From the article:
...at the extremes, it does seem the best breaking balls are at least close to mirroring. None of the top 20 curveballs by whiff rate last year were further than 20 degrees away from perfect mirroring, while that wasn’t true of the below-average curveballs.
The ensuing graph in the article shows that the best mirrored curveballs have an increased whiff rate of 1.6%, while mirrored sliders increase whiff rate by 1.1%.
With all of this in mind, which Cardinal pitchers have the best mirrored pairs?
Giovanny Gallegos, Four-Seamer and Slider
This shouldn’t surprise anyone given how effective Gallegos’ slider has been the last few years. Gallegos has perfect mirroring on his four-seamer and slider combo, with the four-seamer coming out at 1:00 and the slider at 7:00. Here’s how Baseball Savant visualizes it. What you want to pay attention to in this image is the clock face on the left, which is how it comes out of the hand. The image on the right is the spin direction when it reaches home plate, and the difference between the two implies (to quote Baseball Savant) “additional aerodynamic forces at work.” Gallegos’ perfect mirroring between his fastball and slider is why his slider is one of the best in baseball.
Alex Reyes, Four-Seamer (and Sinker) and Curveball
Reyes possess not one, but two pitches that are perfect mirrors with his curveball. Both his fastball and his sinker come out of the hand at 12:45, and his curveball comes out at 6:45. Here’s the graph:
That’s lethal if you’re a hitter. Reyes is hard enough to hit as it is, with his fastball and sinker combo each registering around 98 mph. Then you add in his hammer curveball at 81 mph. On top of everything else, the seams look identical on all three pitches. A hitter sitting dead red might see fastball seams, only for the pitch to wiggle down on a sinker at the last moment at the exact same velocity. Or worse, seeing fastball seams and needing to gear up for the extra queso from Reyes, it comes in at 81 mph and dives down, hard, with above average horizontal break and some of the most vertical break in the game. Alex Reyes lives in video game cheat mode territory.
Carlos Martinez, Changeup and Slider
Only eight pitchers in the game (out of 203) have a perfectly mirrored changeup and slider combination, and Carlos Martinez is one of them. His changeup comes out at 2:15 and his slider at 8:15.
The way these pitches move, in opposite directions, makes the combo that much more effective:
Sure enough, despite a very difficult 2020, these two pitches carried his best whiff rate and putaway rate. While we don’t have Hawk-Eye spin data for 2019, we can see that this combination also boasted his best whiff and putaway rates that season as well.
If you’d like a silver lining for Carlos Martinez entering 2021, his fastball was also very close to perfect mirroring with his slider. “Perfect” mirroring is a 6 hour difference. In 2020, Martinez’s fastball and slider difference came in at 5:45. Just 33 of 312 pitchers were better at mirroring those pitches. If he can tighten up the fastball with spin more similar to his changeup, that would give him three pitches with perfectly deceptive spin from a hitter’s point of view. That’s one heck of a building block to restoring his performance to his former glory.
When looking at the list of pitchers closest to perfect mirroring on curveballs and fastballs, it was hard not to notice that the Cardinals have four others who landed at 5:45- just a tick off from perfect mirroring. Adding in Alex Reyes, who does have perfect mirroring, that gives them five pitchers at 5:45 or better. In fairness, that isn’t a league-leading total. It places them with the 10th most pitchers with 5:45 or 6:00 difference in MLB last season. The other four fastball/curve combos belonged to Genesis Cabrera, Daniel Ponce de Leon, Jake Woodford, and Austin Gomber.
Woodford is an interesting case study. His sinker and his curveball, technically, are perfect mirrors for one another. His four-seamer isn’t too far off at 5:45. The quandary is that he didn’t throw that many sinkers, and ideally you’d want its spin to perfectly mimc the fastball. Moreover, its movement profile isn’t profoundly different from his four-seamer. Still, adjusting the sinker to get a little more life out of it could help both his four-seamer and curveball play up.