On MLB Hitter Development
Part III of III
In this case study on MLB hitter development, we examine all hitters using uHIT Custom from one pro organization.
What you need to know:
Counterexamples with low usage show OPS drops and other warning signs
We Track with XP. They Track with OPS.
As a top-line summary, all players who regularly used uHIT Custom showed substantial gains in on-field hitting. In this case study on MLB hitter development, we will use OPS (and its components, OBP and SLG) from publicly available sources. We tie growths in uHIT performance to on-field via this metric and uHIT’s XP / Pitch (see more here about XP / Pitch). The uHIT XP / Pitch is a measure of how accurately and quickly hitters are learning to recognize pitches and strikes/balls.
Parts I and II: Top-5 Users of uHIT Custom
We gauge uHIT effects by looking at regular users of the training (see more here for Part I and here for Part II). From top-5 in usage (measured by Pitches Completed on the uHIT Dashboard), we found hitters who were regular uHIT Custom users. We looked at top-5 usage for each of the skills worked in uHIT in-season (Pitch, Sub-Zone and Whole-Zone Recognition). The top-5 threshold ensured that the players had done at least 1000 pitches on uHIT in the 11 months of in- and off-season usage. Although usage fluctuated by the demands of the year, this amounted to a usage of ~90 pitches per month (about 20 minutes of uHIT usage monthly).
Even with this small investment of time, the gains in OPS in some cases were tremendous, netting a substantial return on our client’s investment.
Part III: Bottom-2 Users of uHIT Custom
As a set of counterexamples. we also looked at players who did not use uHIT regularly. We regularly get asked ‘how do you know you’re not cherry-picking results?’ or ‘maybe the other training the hitters did produced these effects?’ By looking at hitters in the same organization, we can reasonably say that all hitters’ training outside of uHIT Custom was relatively similar. For instance, they shared the same strength & conditioning coaches, nutritional programs, and live batting practices. Also, there cannot be cherry-picking when we’ve selected players only by how much they used uHIT Custom. Within this MLB organization, there are no other hitters who used uHIT Custom as consistently as the top-5. And we selected the counterexamples with similar dispassion. Specifically, the counterexample hitters were the bottom 2 in training usage, also measured by Pitches Completed on the uHIT Dashboard.
Within the organization, these players provide the best means of being a counterexample that might be generalized to other players who did not use uHIT Custom this season. It’s not a perfect comparison. But considering the many factors of the real-world, this is a great way to gauge what added value (above status quo) uHIT Custom adds. Overall, the bottom-2 hitters’ on-field hitting showed either a downward trend, or clear warning signs about performance.
A Note on Hitter’s Names: Top-5 Users
Getting back to the top 5 players, these hitters averaged at least 90 pitches monthly (1000 pitches all year) across either Pitch or Zone Recognition Training. In this three-part case study on MLB hitter development, we will refer to them anonymously (as we do with the bottom-2). We do this both to protect their non-public data and to illustrate deCervo’s commitment to helping its clients excel (see other MLB studies here). The hitters will be known as:
- Hitter #1
- Hitter #2
- Hitter #3
- Hitter #4
- Hitter #5
- Hitter #6
- Hitter #7
Three of these players hit this usage minimum in both Pitch and Zone Recognition Training (e.g., Player #1). That’s why there are not 10 hitters total (two sets of 5 hitters for each skill). And this is a common observation with our training: the hitters that are serious about part of it are usually serious about all of it.
A Note on Hitter’s Names: Bottom-2 Users
For this post on counterexample hitters, we consider the bottom-2 performers by usage in Pitch and Zone Recognition on uHIT Custom. There are two hitters in Pitch and two in Zone Recognition, making four total. We will refer to them in this post as:
- Bottom #1
- Bottom #2
- Bottom #3
- Bottom #4
These four hitters give us a way of seeing how not using uHIT Custom impacts here the case study on MLB hitter development. With that in mind, it’s time to analyze how these hitters’ performance evolved in uHIT and on-field this year. We welcome your feedback and analysis on these players in the comments below. You can also ask questions on our social media (here or here).
Counterexample, Bottom #1
Counterexample, Bottom #1
Below, we begin by looking at a) Bottom #1’s Assessment, b) the minimal training he began, and finally 3) what he did at the plate.
Questions to consider as we go through this and other players in this case study on MLB hitter development:
- What problems could we see from his Assessment?
- What solutions was he just scratching the surface of before letting the training go?
Bottom #1’s Assessment
Bottom #1 (“B1”, for short) had a decent Assessment in Zone Recognition. His Accuracy of 73% and Reaction Time of 0.446sec put him at an average of 58 XP / Pitch. This put him in the 2nd quartile (top 50-25% of hitters) of this skill.
When we broke down his assessment by zone we saw a preference for pitches (balls and strikes) on the inner half of the plate. Being a right-handed hitter, he either tapped for more strikes inner part of the plate, or did so for balls just off the inside part of the plate. You can see this in the breakdown by Zone Accuracy and Reaction Time below:
Bottom #1’s Preference for Inner-Plate Pitches
On the inner third of the zone, B1 shows 67%, 80% and 88%. But on the outer part of the zone, he shows 50% for all three zones top to bottom. This shows a strong tendency for pitches inner part of the zone, but statistically no ability to discriminate outer third strikes from balls. When we look at the ball zones, inside pitches are correctly taken 33% and 60% of the time, meaning he’s errantly swinging at balls inside 67% and 40% of the time top to bottom. Conversely, when we look at balls off the plate, he’s taking them at 57% and 80%, meaning he errantly swings at them 43% and 20% of the time.
There are two possibilities from this analysis. First, B1 may just be an inner-zone hitter and he could be coached this way. This could be why he shows a propensity for inner plate pitches, either balls or strikes. Second, and more common, he’s not seeing the difference between balls and strikes on the outer third. Furthermore, he’s not registering the feedback given to him in uHIT Custom Training that he is incorrectly tapping for balls and taking strikes. This is a vital skill to learn, regardless of B1’s pitch preferences. And this is a part of his Zone Recognition skill we would target in a uHIT Custom training program.
Bottom #1’s uHIT Custom Training: Stopped By Adversity
Of all org hitters, Bottom #1 (B1) used Zone Recognition for the least amount of measured pitches (only 54). In those 5 sessions, he averaged a higher Accuracy (86%) and and a greater XP / Pitch (80.4). A great part of this improvement was due to him getting slower pitches with less tunneling in these early rounds of training. For instance, the Assessment had been for pitch speeds ranging from 75-90mph (see more about our Assessments here). But on B1’s first training inning, the uHIT Custom program dialed him down to 71-75mph. This greater time caused B1’s Reaction Time to slow down to 0.532sec. But that’s where his training ended.
B1 breezed through four innings of Zone Recognition uHIT Custom Training. But at the 5th inning, he faltered and never got back up. He logged no more sessions of uHIT Custom after this initial failure. This is an important theme to recognize from this case study on MLB hitter development. It shows how a hitter can coast while it’s easy, but give up when he meets a failure. Our goal in training is to guide the hitter (and his coach) through that barrier. It’s always better to do so before they are back on the field. (Contrast this behavior with the success of Hitter #1 from Part I: He failed hundreds of his 2300+ sessions in uHIT Custom, but eventually broke through each of his toughest innings. And we saw the 400+ OPS points he gained from doing so, along with the $2.4M in player value.)
Bottom #1 On-field Hitting: OPS drops
For first year hitters, the best way to evaluate progression over time is to look at pre/post periods of hitting. Fortunately, with B1, we know that on July 25 he moved teams in the Dominican Summer League. So we can take this date as a dividing line to track progress. Unfortunately though, at the same time his hitting was falling off, we saw a decrease from pre-July 25 on DSL Blue to post-July 25 on DSL Red in 2023 (OPS of 0.841 to 0.654, see below from milb.com):
As we know from the org coaches (see Part I), there is no difference in the competition between these two levels. While we can only guess from available data, it is likely that opposing pitchers learned about B1’s weaknesses (maybe the outer third of the zone) and exploited that to negatively affect his OPS. With more training on uHIT Custom, we hypothesize that we would have minimized that weakness and it may have shown up in his OPS. We can only hope that next year we get the chance to help B1.
Counterexample, Bottom #2
Counterexample, Bottom #2
As with Bottom #1 (B1), we begin by looking at a) Bottom #2’s Assessment, b) the quality of his training, and finally 3) what he did at the plate.
A noticeable difference with B2 is that he was a bottom-2 user of one skill training (Pitch Recognition). But he crammed about one week of skill training in another skill (Zone Recognition) during his short time with uHIT Custom. His case illustrates a general trend we see from this case study on MLB hitter development. That is, hitters only improve with uHIT Custom when the training is consistent (see this 8-week case study with another MLB org as an example of this).
Bottom #2’s Assessment
Bottom #2 (“B2”, for short) had clear skill deficits visible in his Assessment on both Zone and Pitch Recognition. In Zone Recognition, his Accuracy of 64% and Reaction Time of 0.418sec put him at an average of 23 XP / Pitch. In Pitch Recognition, his Accuracy of 47% and Reaction Time of 0.411sec put him at an average of 48 XP / Pitch. This put him at about the 50th percentile for both skills.
We broke down his assessment in Pitch Recognition by looking at how his decisions went when he expected one type of pitch and was thrown a different type. For instance, you can see below that when he expected a Fastball and was thrown a Curveball, he took those pitches 33% of the time. But conversely, when he expected a Curveball and was thrown a Fastball, he took those pitches 0% of the time:
The diagonal (upward to the right) shows how often he correctly recognized the pitch he was expecting. Of these pitches, Sliders were the hardest for him to connect recognition to action for (70% Accuracy).
Bottom #2’s uHIT Custom Training: Short & Shallow
Bottom #2 (B2) showed a brief surge of training early on. In one week, he completed one round (9 innings) of Zone Recognition training. This round reduced the pitch speeds drastically from the Assessment (down to 71-76mph). But this added time helped B2 get more time to decide in vs. out of zone, so that he averaged 69% Accuracy (up by 20 points from his Assessment performance).
And then B2 dropped uHIT Custom for one month. At that point, he dabbled in two innings of Pitch Recognition training, netting 12 pitches there. This was the second lowest number of pitches trained in the org for this skill.
Bottom #2 On-field Hitting: OPS drops
As with B1, we look at B2’s pre/post periods of hitting. In his case, he moved teams in the Dominican Summer League on June 12. So we can take this date as a dividing line to track progress. It does not leave a large sample size for the pre-June 12 period (21 ABs). But there is enough the gauge his on-field hitting during this time with a reasonable degree of accuracy. Using this marker in the season, We saw a massive decrease across 2023 from pre-June 12 on DSL Red to post-June 12 on DSL Blue (OPS of 1.322 to 0.632, see below from milb.com):
As we know above, there is no difference in the competition between these two levels. While we can only guess from available data, it is likely that opposing pitchers learned about B2’s weaknesses too. With more training on uHIT Custom, we hypothesize that we would have minimized that weakness and helped his OPS. As with B1, we can only hope that next year we get the chance to help B2.