Too Many Sliders?
“I wouldn’t let a kid at 11-years-old throw a breaking ball, I never threw a breaking ball until I got to high school,” [Tom] Glavine said.
Typically, the rule is that little leaguers shouldn’t be throwing curveballs. The pitch has been blamed for placing too much stress on young elbows, and even a cursory analysis of the mechanics seems to put credence to the credo – it’s a tough pitch to throw. Watching Luke Gregerson throw four sliders out of five pitches to Alex Gonzalez Wednesday night, though, it seemed reasonable to wonder if the slider was also a stressful pitch. Are slider-heavy pitchers more likely to get injured than those that throw the fastball more often?
Let’s look at pitchers since 2008 and set the cutoff rate for slider usage at 40%. Across baseball, pitchers use the slider about 15% of the time, and in our sample of 680 pitchers, only 90 of them failed to use the pitch at least 1% of the time. So nearly 600 pitchers have used the slider regularly in the last three-plus seasons – and only 25 pitchers have used the pitch more than 40% of the time. Those 25 pitchers make up our Slider Group, and naturally Luke Gregerson is included. Michael Wuertz, though, is the king of the hill here. He’s used the slider 64% of the time since 2008, a percentage that usually would be attached to the fastball. Here’s the whole Slider Group, with their fastball and slider velocities and usage rates, as well as a last column with the number of DL trips since 2008.
| Name | FB% | FBv | SL% | SLv | DL Trips |
|---|---|---|---|---|---|
| Michael Wuertz | 31.6% | 90.6 | 64.0% | 85.4 | 2 |
| Mitch Stetter | 42.8% | 84.9 | 57.2% | 78.6 | |
| Brad Lidge | 45.0% | 93.4 | 54.7% | 84.7 | 5 |
| Luke Gregerson | 41.9% | 90.8 | 54.4% | 83.7 | 1 |
| Carlos Marmol | 44.8% | 93.8 | 54.0% | 82.9 | |
| Kiko Calero | 43.8% | 88.3 | 51.9% | 79.7 | 2 |
| Justin Hampson | 28.2% | 87.2 | 49.9% | 82.7 | 1 |
| Jesse Carlson | 49.4% | 88.6 | 48.9% | 80.9 | 1 |
| Jorge Sosa | 44.7% | 92.2 | 47.2% | 85.6 | |
| Bill Bray | 52.9% | 91.2 | 47.0% | 84.7 | 1 |
| Luis Vizcaino | 44.6% | 91.7 | 47.0% | 83 | 1 |
| Doug Waechter | 51.5% | 90.5 | 47.0% | 84.5 | 3 |
| Casey Fossum | 34.1% | 87.7 | 46.0% | 82.8 | |
| Pat Neshek | 43.8% | 86.9 | 45.9% | 82.2 | 3 |
| Dario Veras | 45.8% | 90.2 | 45.9% | 85.1 | |
| Dan Giese | 51.5% | 86.6 | 45.1% | 76.4 | 2 |
| Marcos Mateo | 55.3% | 93.6 | 44.1% | 86 | |
| Justin Speier | 41.1% | 89.8 | 43.3% | 84.8 | |
| Justin Miller | 47.0% | 88.4 | 43.2% | 79.1 | 2 |
| Fernando Cabrera | 52.5% | 91.7 | 42.6% | 81.2 | 1 |
| Sergio Romo | 54.2% | 89 | 41.3% | 77.6 | 1 |
| Mike Gonzalez | 57.9% | 92.4 | 40.7% | 82 | 2 |
| Jon Lieber | 54.5% | 87.2 | 40.6% | 81.7 | 2 |
| Scott Atchison | 48.4% | 91.1 | 40.5% | 86.7 | |
| Dennys Reyes | 50.7% | 89.9 | 40.2% | 83.8 | 1 |
It should be of little surprise that our Slider Group is mostly relievers – and that the only starter, Jon Lieber, was a reliever in 2008. Throwing the slider 40% of the time doesn’t really allow much space for the third pitch that often separates the starter from the reliever. And it may also not be surprising that their fastballs don’t have the most velocity. Where the average major league fastball clocks in at around 91 or 92 depending on if it’s a four- or two-seamer, these guys have an average velocity of 89.91 on their fastballs. That’s not overwhelmingly slower, but then again, if you had plus-plus velocity on your fastball, you’d probably use it more than your slider, wouldn’t you? So this group uses their fastball 46.3% of the time and their slider… 47.3% of the time!
The group averaged 1.24 trips to the DL over the last three years as a whole, but if you focus only on those that did get injured, they averaged 1.71 trips. Thanks to Jeff Zimmerman, we know that relievers had about a 38% likelihood of hitting the DL over this time period. Since these pitchers didn’t all pitch three years in the sample, we have approximately 64 player-seasons represented. In those 64 player-seasons, we have 31 trips to the DL, or a 48.4% likelihood of hitting the DL.
In this sample of 25 players over the past three years, we have have ten surgeries and a major Rotator Cuff injury. Bill Bray, Pat Neshek, Dan Giese and Mike Gonzalez all had Tommy John surgery, a 16% rate that is already far ahead of the major league rate for all pitchers. USAToday reported in 2003 that 75 of 700 major league pitchers had undergone the surgery (10.7%), and since Jon Lieber is also a TJ survivor, 20% of this group has had the surgery. If you zoom out on this group’s careers, you add seven more surgeries and another major Rotator Cuff injury, meaning that this selection of 25 pitchers has endured 17 surgeries and two major Rotator Cuff injuries as a whole over their careers.
Every pitcher is different. We can’t use this work to say that Carlos Marmol is inevitably headed for surgery in the coming years. This is not a comprehensive study, and we cannot make an equation of the results. 40+% slider usage does not equal Tommy John surgery. But it certainly doesn’t look like throwing the slider that often puts you in healthy company.
Cutting down on excess sliders can only be beneficial to your health. Who do you thin Pablo Sandoval got into such great shape this offseason ?
Would have been so much better without the blatant spelling error! Who do you thin = How do you think …
He was just too excited to finally use that line.
Sorry I ruined your day with my typos.
And here I thought he was being intentionally punny
Rerun with SPs, please?
I didn’t actually run this for relievers! What I could do is try it again with 30+% slider usage…
This begs the question of what the incidence of DL trips is for the reliever population at large.
Also, it might be useful to normalize in terms of IP. A guy who pitches 70+ innings a year would be more at risk than a guy who throws 40 innings, of course.
Looking at just 2009 to 2010.
All is for 60 innings 39.5% chance of DL the next year.
RP > 70 innings 35% chance of the DL the next year.
The Sampling error in that one is that if you are healthy enough to throw 70+ innings you are a little more likely to avoid the DL than the general population. It seems like the biggest predictor of future injury is previous injury
I doubt there are many/any SPs throwing the slider at 30%. I’d go with 20% as that is a good number of sliders to be throwing (good=a lot).
Sliders have the general reputation as being the high risk, high reward pitch. If you are a high slider thrower, you know, at some point, you’re going to miss a season. But, the slider is such an effective pitch given its combination of movement and velocity, that’s it literally worth the injury risk.
Curveballs are not as risky as once thought, but they also are not nearly as effective as higher velocity breaking pitches. The “Big Bender” ala Bert Blyleven is extinct. The last one is believed to be killed by Rob Deer. If you don’t throw a hard breaking curve (i.e., highish velocity), you’re better off not throwing one, or throwing it sparingly.
Or … you could look at the number of “sliders thrown” and have the “% slider” be irrelevant.
Liriano does… so we already know the answer.
You and are thinking alike.
Total number of sliders is more important.
By natural events, pitchers that throw more innings are going to often throwmore sliders, which will kind of address the second issue you brought up.
Wainright has one of the best CBs in MLB and its a “big bender” ala Blyleven
He also has/had TRAINWRECK mechanics. Horrible Inverted-W guy.
Inverted W = snake oil.
Inverted W is like the triangle offense in basketball, at one point or another all teams appear to be running it, ditto pitchers and the inverted W.
An inverted W is an M.
I would take a look at the number of actual sliders thrown per pitcher, not a percentage basis. The supposition is that sliders place undue stress on the ligaments and muscles every single time it is thrown. Not sure there is a big enough sample, but I would also break it down by when the slider or hard breaking pitch is thrown.
There is a belief among pitching coaches that as the mechanics break down as a pitcher tires, much more damage can be done by a slider. So a slider thrown in the first inning may not impart the same amount of micro-damage or stress that a slider in the 5th inning creates.
I just published an article mentioning a similar issue, pertaining to Josh Johnson. Works I read cited that throwing curveballs actually was less harmful to one’s elbow than throwing fastballs or sliders because the elbow can withstand more stress when it is in a supinated position (palm facing up) than in a pronated position. You can read my full article at cracketstats.com for a little more detail.
crackerstats.com **
I agree. The curveball was always less stressful, to me, than the fastball.
Though I had nearly -20 mph seperation between speeds. So I wasn’t throwing it very hard
A curveball is probably less stressful on a fully grown, major league pitcher’s elbow than a poorly thrown fastball or slider, but it is awful for a still growing child’s elbow. Even Bert Blyleven didn’t throw curves until high school.
Also part of the reason little leaguers aren’t supposed to throw curves is because they can strike out little kids easily with it. This makes them dependent on the curve and will never learn how to throw a good fastball or changeup
Um…I think that’s an extremely tertiary reason.
One reason you don’t teach little kids any breaking ball or any kind, not even a cutter, is because they have a habit of getting overzealous trying to snap pitches off. If you want a kid to pitch AND stay relatively healthy, it’s imperative that they maximize repeatability. If they’re trying to make balls bend and crackle they’ll probably just succeed in bending and crackling themselves.
Getting back to the topic, slider’s are a more violent pitch to throw and require much more body and arm control/strength than a youth has. A basic curveball can be thrown almost the same way as a fastball. No need to snap off anything. For a slider to move, a quick snapping action is necessary.
More likely a quadrary reason, but I wouldn’t argue with quentary. Its a quandary.
I coach in a pretty successful travel program and this is our secondary reason for not allowing curves for our pre-pubescent pitchers. First is the injury angle. (We’ve actually seen kids as young as 11 need TJ surgery in rival programs.) The crutch/weapon angle is a strong second, however. We are attempting to build great high school players, and we feel that if a young kid learns to pitch using just the FB and CU, the curve, when added, is a weapon. For a kid who uses it young, it tends to be a crutch. He never learns to hit spots or the value of changing speeds and using location to set hitters up, and he usually costs himself velocity – even without a catastrophic injury. If your goal is simply to win 11U trophies, this is less important, and everyone has their own motives.
Very true, Kyle.
Cheeseburger Brett Anderson’s always been at 30% slide pieces.
Sliders killed me. Never had a problem (20+ years of pitching) with the curveball. I threw it right.
Nowadays they are teaching the slider different, more like a cutter. Much less stress on the elbow. Wish I learned that back when!
Take a look at Steve Carlton’s website. He shows his grip and release – its all in the hand and fingers with no change in elbow movement. Incredibly healthy pitcher and the arguably the best slider ever. Food for thought.
On a related note, why is Mike Marshall seemingly blacklisted from baseball? I realize his views are somewhat unconventional, but they are based on scientific (kinesiology) research.
Marshall is extemely quacky.
Last I watched of him, the fundamentals he was teaching were supposedly completey safe on the arm, but could barely produce a velocity of 80-mph.
He’s 68 years old!
I actually am surprised by the velocity findings. When I think of prototypical slider pitchers, I think of Jeff Nelson, Gagne, and Randy Johnson. Johnson is a generational talent who should probably be treated as an outlier, but Gagne and Nelson could really ratch it up with the fastball. (Or at least I remember Nelson as throwing hard–he might have been in the low 90′s as the graphic suggests)
Nelson was low 90s. Crossfire side-armer, sinker/slider.
I don’t recall Gagne throwing a slider. Fastball, change-up, and lollipop curveball mixed in sporadically. At least as a closer.
I guess it’s more of a “slurve.” Point taken–my memory is off.
Bill is right about Gagne. Fastball and Vulcan Change.
The belief that sliders are bad for the arm has been around forever. Someone said many years ago “whenever I throw the slider it feels like an alligator is biting my elbow.” Anybody remember who it was?
Jim Bouton said it in Ball Four when referencing Larry Dierker’s slider.
Thanks for the research. It would be nice to see a study on just SP, because it seems that total number of sliders thrown is more significant thatn percentage.
Also, maybe sort the injuries by time spent on the DL instead of number of trips. And maybe it should only include arm injuries (not sure if you specified that or not).
I’ve been wondering about the stress of sliders. Thought I read somewhere that the Rays are discouraging pitchers from using the slider (not in every individual case, but as an organization). Garza decreased his slider usage when joining the Rays and has substantially increased it since joining the Cubs. Among their current rotation, Shields has never thrown one. Hellickson does not throw one. Price has dramatically reduced his slider usage since when he first came up. Davis and Niemann both throw the slider around 15% of the time. Any one read anything about this?
This is really good analysis. I dont have anything to add, just wanted to say thanks for the good work.
Wainwright’s curve is a serious 12-to-6′er, one of the best in the game.
Blyleven’s was like someone threw a damn frisbee. *grin*
Wainwright’s increased use of the slider might be very relevant to this thread.
He’s also not an inverted-W guy. Any concern with AW50′s mechanics has to do with the height of his PAS elbow at release point. It’s elevated.
Blyleven threw 2 curves. Frisbee and 12-6. That’s how nasty the guy was. And he thinks his best pitch was his fastball.
As for Wainwright, the lack of an inverted W combined with the high PAS elbow is likely why his shoulder is fine and his elbow went bad.
Agreed …
In the mid 80′s, the joke went …
Q: Who has the best curveball in baseball?
A: The same guy that leads the league in home runs allowed.
Blyleven.
About this time, Roger Craig, and the Slider Revolution were taking over. Slider is harder to read/react to than a curveball, higher velocity, easier to control. Lots of risk though.
There is also an aspect that the slider is “more macho” … don’t underestimate how much that plays into the mindset of a pitcher ages 15-23.
The inverted-W is when, during the stride and hand seperation, both elbow travel higher than the shoulders.
Peavy and Stasburg are erroneosly assigned the inv-W. The issue with those guys is that their PAS elbow travels toward 1B, behind their body.
Nice article. Quick correction though, in paragraph two, you say “Only 590 of them failed to use the pitch at least 1% of the time.” I’m pretty sure you meant 590 of them did use the pitch at least 1%, or 90 of them failed to.
thanks! and fixed!
A little off topic but to some of the commenters – it’s my understanding that you certainly never ‘snap’ or twist your wrist or arm when you’re releasing a breaking pitch. I threw a great curve in HS and I was always taught to let your grip do the work.
A slider and curve are both varying degrees of a ‘breaking ball.’ The ball simply spins forward instead of backward. If your fingers come straight down over the front of the ball, it’s a curve. If they’re a little more tilted, it’s a slider.
Arm problems can result, because when you naturally throw anything your palm faces forward/down at release and then pronates (palm turns to face out, thumb points down). When you release a breaking pitch your hand is facing IN (thumb points up) and thus you do not get the ‘natural’ pronation of the arm. I had elbow problems specifically because of this, and it makes sense that the slider would be worse on the arm because you’re throwing it harder than the curve.
Sorry for the slightly off-topic, long post. I’ve always been interested in pitching mechanics and despite coming off like a know-it-all, I am curious to see if others have been taught a different way or if there is any literature on the subject.
I gave up baseball at the start of high school to focus on basketball, but when I was pitching I learned a curveball (from a former minor league pitcher) that involved “rolling” my arm down around the ball. Basically, the movement of my arm was the same as my fastball, but my palm faced me, and my hand went on top of, and then in front of, the ball as I released it. I could see another pitcher using the same motion, and, in trying to throw the pitch with more break, snapping their arm around the ball. I have no idea how common that sort of curveball is, as I hadn’t been using it for very long before quitting, but take that for what you will.
Yeah, that sounds pretty similar to the way I was taught. Like you said, it can be tempting to try to snap your wrist when throwing it which I’m sure is pretty rough on the elbow.
To be able to draw any conclusions from this study, you need to have a control group. It would NOT surprise me at ALL to hear that the average number of DL trips for pitchers in general since 2008 in 1.24! These 25 pitchers had 31 DL trips, but almost 1/6 of those are due to a single pitcher.
Actually, a better study would be to do this analysis for ALL pitchers who have pitched since 2008, then check pitch tendencies, pitch counts, age, appearances, etc. to get a more global idea of what leads to injuries…
I ran a large regression on a dataset mined from my injury DB including PITCHf/x data. I wrote about this on THT a few weeks ago. You can find the article here:
http://www.hardballtimes.com/main/article/pitching-injuries-a-pitchf-x-look/
Can we do a t-test or ANOVA with groups of pitchers who use other pitches 40% of time (i.e., fastballs, curveballs, knuckles, etc)
I realize that it falls outside the timeframe of this brief study, but Justin Speier went on a DL stint in 2007 that effectively ended his career.
I’m sorry if this was already pointed out but I couldn’t read through the thousand comments. I was kind of confused by the set up of this article which implied that curve balls are implicated in the most stress on the arm while sliders are this unknown silent killer. Anyone who has grown up playing baseball in the past 20 years or so has surely heard that the slider is unparalleled in it’s strain on the elbow because it exposes the UCL to the most stress. Curveballs gain so much attention in little league because it is the first breaking pitch most of the unqualified coaches teach incorrectly to young pitchers. When thrown properly a 12-6 curve ball should put very little stress on the elbow.
On a separate note, I really liked that you looked at the kinds of injuries more closely which is what I was looking for when I opened the article. Obviously 25 oblique injuries (just first thing that came to mind because pretty much the entire MLB seems to have had one in the past couple of years) can’t necessarily be linked to pitch selection.
with all of the new video technology coming out I would love to see more biomechanics filter into the analysis analyzing arm slot, hip and shoulder separation etc.