Grades on the 20-80 scouting scale are subjective by nature. Similarly, the scores that I dole out for the pitching mechanics report cards are based on what my eyes tell me. Each scout sees the player-evaluation world through a unique lens that has been shaped through experience, giving rise to an art of scouting that is rooted in personal observation. The greatest challenge in scouting is also the most fundamental aspect of the process: to convey with words what is seen with the eyes. The grades are only as powerful as the communicative value that the numbers carry, which should be sufficient motivation for an evaluator to be transparent with his process.

I laid the groundwork for the grades in my BP debut, outlining an emphasis on the kinetic chain of movement when pitching a baseball. The chain metaphor signifies the ripple-like influence of the pitching delivery, where a kink in the early links of the chain can lead to inefficiency further down the line. The order of operations is critical within the kinetic chain, and proper sequencing is necessary for peak efficiency, with timing as the key ingredient of the pitching motion.

While the grades are subjective, the evaluations have a quantitative basis, thanks to years spent analyzing motion-analysis data at the National Pitching Association. State-of-the-art technology allowed for the precise measurement of the physical components that make up the grades—I analyzed thousands of pitches, both numerically and visually, thanks to high-speed cameras and software that we specifically designed to evaluate pitchers. My everyday job was essentially a baseball boot camp for pitcher analysis.

A video-analysis background has come in handy in the era of and GIFs, and I look forward to a day when the game-tracking tools of f/x technology enable the quantification of these events on the field. In the meantime, we will have to lean on a bit of educated guesswork. Some of the following descriptions will be a review for those readers with an advanced degree in Pitchology, though I hope that some player examples representing individual grades will enlighten our sofa-scouts in training. Keep in mind that individual 20-grades are very rare among the major-league population of pitchers, as few players can survive at the highest level with such a glaring mechanical inefficiency.

With due respect to the kinetic chain, let’s tackle the grades according to sequence.

What to watch: When I assess balance, I anchor on the position of the head relative to the pitcher’s center-of-mass. A pitcher with strong balance will have minimal lean during the motion, stabilizing the head above the body throughout the delivery. This means that a pitcher who leans toward first or third base during maximum leg lift, whose head lags behind the body en route to foot strike, or who lowers his center-of-gravity after max lift (a “drop-n-drive” delivery) will be dinged on the balance grade on his mechanics report card. The grade covers the time period from set-up through release point, and a pitcher who leans too far forward or who falls off to the side near pitch-release will take an associated hit to the balance grade. Ideally, I like to see a pitcher who sets up the delivery in an athletic, balanced position, with some natural flex in the knees that will help to maintain dynamic balance in the vertical plane that is consistent with the slope of the mound.

What 20-80 looks like:

20Carlos Marmol

40Randall Delgado

60Zack Greinke

80Matt Cain

Development Path: When a pitcher lacks balance, it can be a symptom of poor conditioning, coordination, or technique. There are pitchers who set up the delivery from an imbalanced position—some players will shift their weight over the back foot when pitching from the stretch, and many pitchers will set up in a tall position that lacks athleticism. These players could improve their consistency by adding some flex to the knees in the set-up position, with the head positioned above a lower center-of-gravity.

To determine the appropriate amount of flex in the knees, a coach would lean on the player’s natural balance point, consistent with the level that the player exhibits during the momentum phase of his delivery. But standing tall without athleticism is like an outfielder standing flat-footed until the moment he begins to run the ball down. Balance issues are commonly related to functional strength, and the concomitant ability to sustain the high-energy motion that is necessary to throw baseballs at or upwards of 90 miles per hour for a living.

What to watch: To evaluate momentum, I take into account the speed and direction with which a pitcher travels from first movement to foot strike. I look for a pitcher who initiates his momentum directly toward the target from first movement, taking advantage of the set-up position (with both feet planted) to propel down the slope. Another common technique is to drift back toward second base as the pitcher reaches maximum leg lift, and then to initiate forward momentum from a stork-like position on one leg.

There is a related coaching strategy that decrees that a pitcher should “stop at the top” of his motion (i.e. max leg lift) in order to find a balance point, halting his momentum while steadying his frame before charging toward the plate, though any method that interferes with a pitcher’s natural progression is likely soiled with inefficiency. I have often described pitchers as having “two gears” in their momentum, starting slowly and then shifting to a faster speed after maximum leg lift—for these pitchers, the 20-80 grade considers both the early movement and the later burst to the plate. I also consider the windup versus the stretch when determining the grade, and many players will have better momentum from the stretch due to the common emphasis on a quick pace to thwart the running game.

What 20-80 looks like:

20Tyson Ross

40 Jeremy Hellickson

60Clay Buchholz

80 Tim Lincecum (2011)

Development Path: My general rule for momentum is “to go faster,” as the vast majority of pitchers have been told not to “rush” their delivery, an instruction that is so pervasive that any pitcher who does create an obvious burst to the plate is at risk of being branded with the “violence” label. The rush to judgment is part of a widespread paranoia with regard to pitcher injuries and the presumed role of “effort” in the delivery, though a balanced pitcher who possesses structural integrity can safely take advantage of the extra charge.

Many pitchers who increase momentum will see an associated benefit to their timing, especially for those who have been raised under the “don’t rush” doctrine, as the quicker motion will effectively shrink the time-window for the motion to fall off-track. A vague understanding of what causes injury has led to widespread paradigms that are increasingly conservative yet not necessarily more effective, a phenomenon which is at least somewhat due to the dichotomy of a baseball community that eschews violence yet craves velocity.

What to watch: Torque is heavily associated with arm speed and therefore pitch velocity. The pitchers with the most efficient torque can effectively use the body to transfer kinetic energy, maximizing hip-shoulder separation rather than relying on sheer arm strength to add rotational velocity. The way to assess hip-shoulder separation is to look at the pitcher just as he begins trunk rotation, which should take place just after foot strike for a well-timed delivery, to evaluate the position of the shoulder axis as it compares to angle of hip rotation. A pitcher who loads the upper body by twisting the torso will increase the angle of hip-shoulder separation, as will a pitcher who allows the hips to rotate further by delaying trunk rotation after foot strike.

What 20-80 looks like:

20Mark Buehrle

40Tommy Milone

60Matt Harvey

80 Aroldis Chapman

Development Path: Momentum and torque are the power grades, representing the kinetic energy that is flowing through the system, and pitchers who grade well on these two categories tend to fall into the “violent” bin. Part of the explanation for the assumed violence is that high-energy pitchers often struggle to stabilize the motion, resulting in issues with repetition and pitch command. There is generally a give-and-take for a pitcher in which more kinetic energy results in less stability, at least until the player learns to harness his ideal delivery.

Player signature dictates the relative proportion of hip rotation versus upper-body load, and both elements can be improved through targeted training. A pitcher can increase hip-shoulder separation by working on functional flexibility and core strength to safely add greater twist to load the shoulder-axis. Alternatively, or in addition, he can carefully extend the amount of time between foot strike and the firing of trunk rotation. In this sense, functional strength supports balance, while functional flexibility underlies torque. There are other factors, such as scapular loading, which can further increase torque and velocity, but such techniques involve muscle groups that are commonly underdeveloped, which puts physical conditioning at a premium in order to minimize injury risk.

To be continued… 

Thank you for reading

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Doug...Fantasic article and visuals! I grew up as a pitcher and still maintain a massive bias toward the science. I look forward to the continuation of the series....Mark
Many thanks. Mark!

I never knew that physics could be so cool until I started learning the real science behind pitching mechanics. Personally, I find it fascinating that there can be such a massive gap between conventional wisdom and reality.

Hey Doug...I grew up trying to emulate everything Tom Seaver. How would he grade out on your 3 point scale?
Seaver was awesome. His balance grade was hurt a bit by some lean back toward 1B at max leg lift, and his head trailed behind the center of mass, but he finished with strong balance and posture (which will be covered in Part Two) - averages out to about a 50 grade. His momentum was excellent, probably a 65 overall, and I have seen pitches where it graded out as an easy 70 from the windup. His torque was elite, with huge upper-body load and great timing of trunk rotation - his torque grade was a solid 70, and reached 80 during his peak.

You picked a helluva player to emulate.
Love this article. The gifs are great.
This is wonderful. The GIFs make this so easy to follow.
Really awesome--just out of curiosity though, how the heck are Timmy's mechanics legal? I thought you had to toe the rubber the entire time the ball was in your hand. He's getting a couple extra feet towards home plate. I've heard Jordan Walden does the same thing?
Awesome observation, jfribley.

Actually, almost all pitchers leave the rubber in the later phases of the delivery. In fact, it is extremely difficult to physically keep the foot in contact with the rubber at all times.

If you look at the Timmy GIF, you can see how his back foot carves a line in the dirt from where it leaves the rubber through release point. We call this the "drag line," and pretty much every pitcher has one. In fact, it is a great indicator of the pitcher's positioning at release point, and we use the "drag line" as a marker when lining up pitchers on the rubber when they set up. Meanwhile, the length of the drag line is an indicator of how far forward a pitcher's momentum takes him.

It is one of those things that often goes unnoticed, because of an overwhelming tendency to ignore the lower-body when watching a pitcher throw a baseball.

Walden is a different case, though. His back foot essentially "hops" off the rubber, with some slight elevation just before foot strike, which is a very odd trend indeed.
Doug, this is great work. I came for Jason Parks, but I am staying for the pitching analysis. Still love Parks though.
Very cool article, love the visuals, Matt Cain looks so smooth and the super slow motion lincecum is just plain fun to watch

And oh how I would love to see a report card on marmol, as a cubs fan I have seen his whole career and I am still shocked by how bizarre his mechanics are

Anyway this is my favorite series on BP, keep up the good work

Thanks, Andrew!

I could not think of a greater way to exemplify the visual aspect of balance than to put Cain and Marmol side-by-side. They are a testament to the value of functional strength - Marmol might beat Cain in arm wrestling, but functionally Cain is miles ahead!
Great article. One thing that I'm explicitly missing in some places -- though it is implied -- is the why.

Why does a pitcher need great balance? What does an 80 balance do for Matt Cain? More resistant to injury? More consistency in performance? Higher velocity?

Fair point, Alan.

I tried not to repeat too much of the material from other articles, where the "why" has been covered pretty extensively. That said, the point of this series is to provide a Cliff's Notes version of the grading system, and a "why" is certainly relevant.

So here is a brief explanation as to the "why":

Balance - balance allows a pitcher to repeat the positioning aspects of his delivery, and to support a stable motion. Great balance is an underlying ingredient of great pitch command.

Momentum - Greater momentum adds kinetic energy to the system, and through our NPA experiments we discovered that the lower body is responsible for about 20% of a pitcher's velocity. Momentum will also get a pitcher closer to the plate, which increases perceived velocity and allows for (relatively) later movement on breaking pitches.

Torque - More torque = more velocity, and does so in a way that recruits energy from the body rather than rely on pure arm strength.

Some of these elements are related to injury risk, which I covered in this article.

I hope that helps, and thanks for reading!
Thanks so much for the response!
Ross and Buehrle get 20 grades on the power categories. Roughly how much could they improve their velocity by being league average?
Any adjustment would require the functional strength and flexibility to support it, and in that sense the degree of improvement would depend on pitcher conditioning. But if they had the underlying structural integrity, then both pitchers could add some velo through more efficient mechanics.

Buehrle has more room for improvement, because torque is more closely linked to velocity, whereas Ross would see more of a benefit to his release distance / perceived velocity / pitch break.

Theoretically, Buehrle could add a few ticks (~3 mph or more) with average torque. But that assumes that he is flexible enough to produce that level of hip-shoulder separation, and that he could do so without throwing his timing out of whack.

Average velocity is around 90-91 mph, and Buehrle averaged 86-mph on his FB this year. Torque accounts for a big chunk of that difference, but his intrinsic arm strength and other factors also play a role.
Really awesome, this helps a ton. Thanks, Doug.
This is awesome
Love this
Fascinating stuff! Who is a pitcher with close to 80 grades for all 3, or 80 grades in 2 of the 3 categories?
Great question.

There is nobody in the majors that is close to 80 on all 3 of these particular grades, but there are a couple of guys who are well above average on all 3 (60 or better), with 80 spikes. Off the top of my head, Verlander is near the top of the scale for torque and has momentum that is probably a 65-70, though his balance is more like a 55-60. Strasburg has 80 torque and 60-65 balance, and in his rookie year he had 60+ momentum, though I graded him as a 55-momentum earlier this year. Felix Hernandez might be a 65-70 on all three measures, which is incredible when you consider how far his mechanics have come along during his career. His balance and posture used to be a mess, and to turn them both into assets is simply awesome (as if he wasn't good enough on raw talent alone). I should do a write-up on King Felix's development - I'll add it to the list.

The best candidate for your question has already retired, but he was pretty good during his day.
I always remember Greg Maddux being noted for his mechanics. How he was always positioned well after throwing and a repeatable delivery. Does he grade out well? Phenomenal series....
Thanks, Todd!

Maddux had incredible mechanics, and he will be featured in an upcoming article for my "Good Old Days" series. Some folks might be surprised by his power grades (torque and momentum), but nobody will be surprised by his insane repetition grade.

Stay tuned ...
I actually yelled out loud while reading this article, thinking about the number of times my pitching coaches had me pause mid delivery, balancing on one leg, before going towards home plate. I never understood the logic behind it, and it's both validating and frustrating to hear that it does in fact slow down a pitcher's momentum. Fascinating article!

I keep hearing that Trevor May lacks consistent command and can be wild. After reading this article and watching some video, it looks like his balance falls somewhere between Delgado and Grienke... am I being too optimistic?
Haha, I hear ya, Zeustis! The logic behind that instruction never made sense to me, either. It seems to me that if you start balanced and stay balanced, then you shouldn't need to "find a balance point."

Unfortunately, I have not yet had the opportunity to watch May pitch, but players his age often struggle with balance before figuring out how to get into functional pitching shape. As I alluded to with the Felix comment above, balance is an aspect that often improves with age, so there is plenty of reason for optimism with May.
Just wanted to say that this is one of the best features ever at BP! I always talk to scouts at ML games about this rating, but to see it demonstrated and explained with video is a big plus. PLEASE do this with positions like catcher, SS and batting. Great stuff!
I would encourage BP to focus on producing fewer, high quality articles such as the Raising Aces series. This is the type of article that justifies the subscription.