The advent of the two-wild-card system has sucked a bit of the life out of divisional bragging rights, particularly in a year where the World Series was fought between two teams that failed to win their own divisions. So allow me to inject an extra dose of intrigue with some division-specific awards by highlighting the pitchers in each division who fall on the extreme ends of the mechanical spectrum.

The awards cover each of the baseline categories on the mechanics report card, including balance, momentum, torque, and posture. We will turn our attention away from repetition temporarily, though consistency of mechanical timing will play a role in the final crowning of the pitcher with the division's best mechanics.

We start the series on the left coast with the American League West, and will transfer over to the senior circuit before heading east.


Best: Hisashi Iwakuma, 70 grade

Iwakuma has one of the more efficient deliveries in the game, and at the core of his motion is double-plus balance that forms the foundation of his mechanics. His balance is strong in all three planes, with minimal drop to his center of gravity and a stable head position that stays above his center of mass throughout the motion. There is almost no lateral head movement from leg kick through release point, culminating in near-perfect posture. The Seattle right-hander beat out a couple of his teammates, Felix Hernandez and Erasmo Ramirez, as well as Oakland's Jeff Samardzija and Houston's Collin McHugh for top honors in the balance category for the AL West.

Worst: Kevin Jepsen, 35 grade

Jepsen loses balance in every direction. He starts with a big drop after max leg lift, lowering his center of gravity during the stride phase. He loses lateral balance in both directions, hunching over to the third-base side during his stride and then redirecting his imbalance to the first-base side as he approaches foot strike through release point. Jepsen also has below-average balance in the Z-plane, with a head that trails his center of mass during the stride. He actually finishes with strong posture, which is surprising when considering all of the obstacles to stability, though his lack of balance often manifests as poor repetition and shaky pitch command.


Best: Tony Sipp, 65 grade

Sipp rockets through the stride phase of his delivery, and though his flailing limbs give the impression that he is out of control, the southpaw actually does a good job of keeping an efficient line to the plate. There are plenty of other issues with his mechanics, from a general lack of balance to untethered arm action, but the momentum is the one feather in Sipp's cap. With 70-grade speed and a 60-grade route of efficiency, Sipp earns a 65-grade overall in the momentum category for his division, besting starters such as Hector Santiago, Sonny Gray, and Yu Darvish.

Worst: Nick Martinez, 30 grade

Martinez has an extremely short stride, even when pitching from the windup, as his naturally-low leg kick and pedestrian pace to the plate conspire to limit his forward progress from rubber to target. A pitcher can be deceptively slow when he has quick leg movements, but there is nothing deceptive about Martinez's momentum, and he slows down just before foot strike to further dampen his score in the category. The only thing keeping Martinez from an even lower grade is the fact that his first move is directed toward the plate.


Best: Felix Hernandez, 65 grade

There is a very strong connection between torque and pitch velocity, so the highest grades for hip-shoulder separation are typically tied to the hardest throwers in the game. In the case of the King, however, the high-level torque allows him to sustain plus velocity with an efficient use of the kinetic chain. His torque is equally strong whether he is throwing a fastball or a changeup, allowing him to mimic the arm action and add to the deception of el cambio. He utilizes some loading of the upper-half to augment separation, but the key to the King's torque is a heavy delay of trunk rotation that allows his hips to rotate prior to pulling his trigger.

Worst: Colby Lewis, 30 grade

Lewis has a delivery that has been completely drained of power. His momentum is very low, putting him in the running with Martinez for worst in the division, and the torque grade scrapes the bottom of the barrel. He has little to no upper-body twist, while his hips and shoulders are nearly wired together to produce the separation of a knuckleballer. He doesn't throw especially hard, but it's somewhat surprising that Lewis can hit 90 mph considering his soft-torqued delivery.


Best: Yu Darvish, 80 grade

Darvish doesn't always have perfect posture, occasionally slipping to a 70-grade, but he has the ability to scrape the top of the scale even when pitching at high intensity. He sustains a spine angle that is nearly 90 degrees to the ground, although his relatively-high angle of shoulder abduction distorts his jersey to enhance the perceived tilt. The Texas right-hander has elite posture regardless of which of his 17 pitches he is throwing, including the sub-60-mph eephus that he has been known to uncork on occasion. Iwakuma ran a close campaign in the AL West to finish in second place in this category.

Worst: Jered Weaver, 30 grade

Weaver has one of the more odd deliveries in the game. He strides extremely closed, stepping outside the rubber as if he is aiming at the third-base dugout. Weaver then contorts his spine to come back toward the plate, resulting in a deceptive trajectory but a shallow release point; the combination of the tight-angled stride and the severe spine-tilt act to extend the flight path of every pitch he throws due to the stunted release. Weaver's posture takes the division's low score due not just to the severity of glove-side tilt, but also the early initiation of his cock-eyed lean.


Best: Yu Darvish, A- grade

There was a close race for the best delivery in the AL West, with Darvish and Iwakuma both among the select group of pitchers who clear the A-grade threshold. The stability components are elite for both pitchers, and each features a report card that is saturated with plus grades. In the end, Darvish earns the nod for the division's top mechanics due to his integration of plus power without sacrificing stability, as well as a mechanics report card that earns a 60 grade or higher in every subject. His ability to repeat the delivery is much better than his walk rate suggests, as the extreme movement on the right-hander's pitches add a heavy degree of difficulty in locating every pitch that he throws. Add it all up, and this hired gun has the trustiest steel in the AL West.

Thank you for reading

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This post does a really good job of illustrating the difference between good and bad mechanics. Thank you!
Thanks for the kind words, Bryan, and I think that the pics and vids are a necessary communication tool within the world of pitching mechanics.
Doug, I love your articles, and this is some of your best work.

Do you think it's a coincidence that the two best deliveries in the division belong to foreign-born players, or does this speak to something more broadly about how pitching mechanics are taught here in the States?
It's not a pure coincidence, in that balance and posture are highly-valued characteristics in Japan, and those elements are a relative strength for most of the pitchers from NPB.

In the States there is more of a focus on creating angles, and stability is often sacrificed in the name of a tall release point or a deceptive arm slot from a closed angle.
If you really want people to see what you are talking about,it would be helpful to post your videos in slow motion if possible.

Also mechanics are very individualized & what are termed "good mechanics" are only good for that individual pitcher. You want to find an individual player's good mechanics,chain back from a pitch that he executes well. That will tell you what HIS good mechanics are. IMO, in general pitchers spend too much time working on mechanics & not enough time making pitches. The game is 100% about making pitches. Well executed pitches produce the right mechanics for that pitcher.
I agree with you regarding the individualized nature of pitching mechanics (especially as it relates to arm action/arm path), but I disagree with many of the other points raised here.

For starters, though subjective interpretations of "good" and "bad" are often tied to the individual, there are certain absolutes on which to anchor, and these are the categories that are highlighted here (as well as in the report cards). Proper balance is an essential ingredient for every athlete in every physical endeavor, and though conditioning might dictate (for example) the pitcher's ideal balance height, the ability to sustain a stable head position above the center-of-mass is an absolute from which every athlete can benefit. The one exception here is momentum - not every pitcher would perform better with 80-grade momentum, but those who can sustain balance and timing with that momentum reap benefits that low-momentum guys fail to realize.

I also have to ask: what defines a "well-executed pitch?" Mechanics are part of the process that results in what a pitch does and where it ends up, so by definition mechanics are directly involved with pitch execution. You can't have one without the other, as mechanics are a necessary ingredient to pitch execution (not the other way around). Telling a pitcher to "execute his pitches" won't go very far if you don't provide a "how," and that how is rooted in mechanics (supported by drills and conditioning).

I do agree with much of the theory behind backwards chaining, anchoring on what a pitcher did to achieve a "well-executed pitch," but it requires mechanical knowledge to then address the kinetic chain correctly without anchoring on unlinked mechanical elements. One also has to account for the possibility that a pitch has a desirable outcome despite a poor process, and a failure to recognize the mechanics will lead one to make false attributes for success (this is pretty common in the baseball world).

Finally, this generalization - "too much time working on mechanics & not enough time making pitches" - runs contradictory to nearly every pitching lesson and bullpen session that I have ever experienced.
My take was & still is that we spend too much time coaching/verbalizing mechanics. Certainly we have to coach mechanics, but we need to find the "sweet spot" & find a way to make mechanical adjustments without being so cognitive.I've seen way too many sides where there is a tweak after every pitch & the size & depth of info is suffocating.For me, create a goal(drill environment) to accomplish the desired fix & let the pitcher figure it out.The best lessons are self taught.The coach/teacher is nothing more than "guide rails" to keep the athlete moving in the right direction.Truth be told, there is more than one pitcher who would say,if he could,"just be quiet & let me figure this thing out." Again you have to find the "sweet spot" relative to each pitcher & his needs at that time.

As far as balance is concerned, it's dynamic & is all centered around the most efficient means of applying force at the time of release.(Keep in mind that repeating mechanics is a VERY tough gig.They can't repeat their signatures no matter how much time you give them)

I'm in total agreement on the momentum issue with the one caveat being that the more momentum that you can carry through your delivery relative to body control,the better.

The how of executing a pitch is giving the pitcher a well defined goal & see how he organizes his body to accomplish that goal.If it doesn't play out, then maybe you need better more defined goals. Creativity plays a huge role in this process.

In teaching/coaching "specificity" is the #1 most important element in the process.If a large % of the preparation is not specific to the actual game then the outcome will be in question. In times of stress(which occurs numerous times in games), athletes refer back to their point of focus.In pitching,if too much focus is on mechanics then that is they will revert to.the result of mechanical adjustments during games is not good for most pitchers. I'd rather it be making pitches/adjustments(location adjustments) when stressed. I think that gives you the best chance to have a positive outcome.

Really like your work.