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.

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!

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!

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.

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.