On MLB Hitter Development

Part I of III

 Dec 4, 2023

In this case study on MLB hitter development, we examine all hitters using uHIT Custom from one pro organization.

What you need to know:

20 minutes monthly in uHIT Custom, led to $2.365M in realized player value.

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. 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

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.

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).

Hitter #1

Hitter #1: Mid-Season Trade, $2.365M Net Gain

Below, we provide an excerpt of analysis provided to coaches in our client organization. (This is an example of our uHIT Analysis service we provide pro and elite college clients. Please contact here to learn more). Hitter #1 had just been dealt in a trade with one other player for a high-value relief pitcher (more on that below). We focus here on his time using uHIT Custom while in the organization of our client.

As a brief monetary aside, Hitter #1’s 2022 signing bonus was $10,000 and the high-value pitcher’s 2023 season contract was $4,750,000. As one of two players dealt, we can estimate Hitter #1 and the other traded player’s value to be equivalent to roughly half, or about $2,375,000. Minus a $10,000 signing bonus, this trade netted our client $2,365,000 for Hitter #1’s increase in value while training with uHIT Custom. (As a comparison, the organization invested $23,000 in uHIT between 2022-23) This economic analysis shows an example case study on MLB hitter development that manifested on the all-important cost side.

Questions to consider:

1. What comparable value is there for swing speed training?
2. Can techniques like occlusion training or strength & conditioning be as easily tied to player value?

Hitter #1: uHIT Custom Super User

One week after Hitter #1’s trade to his new team, we provided the following analysis on his time with our client:

Hitter #1 has been a super user on uHIT. He leads everyone with 6865 pitches (pitch recognition) and 2845 pitches (zone recognition) done.

In zone recognition, he currently averages 81% Accuracy, having started at 68%. 92.5 XP / Pitch is where he sits now, having initially assessed at 34.8 XP / Pitch. This shows us he’s getting faster and better at pitches in/out of the zone.

In pitch recognition, he’s doing great too. At his last re-assessment, he had 85% Accuracy, having started at 61%. 74.9 XP / Pitch is where he sits now, having initially assessed at 38.4 XP / Pitch. This shows us he’s getting faster and better at recognizing pitch types too.

Hitter #1: On-field Performance

On-field we are seeing incredible results for Hitter #1 too. Last year, he hit a 0.621 OPS with 0.313 SLG. This year he’s raised his OPS by 60+%, hitting 1.075 OPS with 0.611 SLG. His OBP is definitely better (+156 points year-over-year), but his SLG is the big driver here. It nearly doubled year-over-year.

Going back to his uHIT stats, the XP / Pitch are much higher since beginning training in some part because of Accuracy improvements. But the big change is coming from faster right calls (better Reaction Time, esp. in zone recognition).

You can see a screenshot of Hitter #1’s data from milb.com below. It’s worth noting that Hitter #1’s performance on his new team (“DSL ROYB”) was not as good as when he was with our client (for a more detailed look, please contact us here):

Hitter #2

Hitter #2: Doubled OPS, Same Level of Pitching

Some hitters develop a preference for particular aspects of uHIT. Hitter #2 is an example of such a hitter. He was a super user of uHIT’s Zone Recognition Training. As a case study on MLB hitter development, here we look at a hitter narrowing focus on one hitting skill. Second only to Hitter #1 in zone training, Hitter #2 logged 2016 pitches.

In zone recognition, he averaged 71% Accuracy at the close of the 2023 season. We compare this to where he began his uHIT career at 66%. There is a more global measure of his recognition when factoring in decision speed via the XP / Pitch. 74.1 XP / Pitch is where he finished the season, having initially assessed at 59.5 XP / Pitch in the beginning of the season. This shows us he got faster and better at pitches in/out of the zone.

Hitter #2: On-field Performance

We saw great results on-field for him too. With Hitter #1, it was possible to do a simple year-over-year comparison between 2022 and 2023. Here though, Hitter #2 only has one season of data. So we modify our comparison technique to look at a sufficient number of ABs at the start and at the end of the season.

As a comparison, we can look at the 22 ABs he began 2023 with at DSL Blue. We can then compare those ABs to the rest of his season at DSL Red afterwards. On DSL Blue, he hit a 0.322 OPS with 0.091 SLG. At DSL Red afterwards, he more than doubled his OPS, hitting 0.807 OPS with 0.380 SLG. His OBP is definitely better (+196 points Blue-to-Red), but his SLG is the big driver here. It more than tripled from the start of the year. (Important: DSL Red and Blue are comparable levels of play. As our client told us, “there is virtually no difference between these leagues of play in the Dominican Republic).

You can see Hitter #2’s on-field hitting performance excerpted from milb.com here (for a more detailed look, please contact us here):

Hitter #3

Averting a Disaster for Hitter #3

Hitter #3 also demonstrates how some hitters develop a preference for particular aspects of uHIT. Like Hitter #2, he was a super user of uHIT’s Zone Recognition Training.

He was third behind Hitters #1 and #2 in this training, having logged 1956 pitches done.

In zone recognition, he averaged 63% Accuracy at the end of the season. We can track his progress from where he started at 57% in the beginning of the season. The real warning sign with this hitter though was apparent from his XP / Pitch. At season-end, he averaged 51.0 XP / Pitch. This is a rosy outcome compared to where he began, having initially assessed at -25.3 XP / Pitch (yes, that’s a negative sign). This is a great case study on MLB hitter development because it shows what peril a hitter can be in before any signs are visible on-field. So let’s pause for a moment to understand what it means to have a negative XP / Pitch. It means on average that Hitter #3 was taking pitches in-zone and swinging at pitches way before he could see them go out of zone.

But he ended the season by going more than 100% in the opposite direction as he learned his in-zone/out-zone skills (-25.3 to +51.0).

Hitter #3: Performance On-field

We saw moderate gains in Hitter #3 on-field. Last year, he hit a 0.638 OPS with 0.341 SLG. This year in 2023 he upped his OPS, hitting 0.655 OPS with 0.363 SLG. If we look at what changed year-over-year, it is clear his SLG was a bigger driver (+22 points) than his OBP. In fact, his OBP was slightly down (0.297 to 0.292). Going back to his uHIT performance, this trend is somewhat indicated by what we saw in his training. Why is that?

OBP is a good measure of how a hitter makes a decision to get on-base. As far as OBP is concerned, that decision could be a duck snort to right, or a line drive triple down the line. But OBP is not as good of a measure of how quickly and accurately he makes that decision. That has a better analog in the SLG. We can illustrate simply by considering two hitters deciding to swing at the exact same pitch. If the first hitter decides a little sooner than the second hitter, he will be able to put a better swing on the ball. As a result, the first hitter could get on-base with a triple, while the second hitter could get on with only a single (maybe even a duck snort). Both got on-base. But the first hitter took more bases in that at-bat.

The same phenomenon appears to have happened to Hitter #3. As his decisions became faster and more accurate, his XP / Pitch showed a remarkable turnaround (-25.3 to 51.0). This played out on-field in his SLG (0.341 to 0.363). But his Accuracy did not change appreciably (57% to 63%). And this too played out on-field with a minimal change in his OBP (0.297 to 0.292).

You can see Hitter #3’s on-field hitting performance excerpted from milb.com here (for a more detailed look, please contact us here):

Hitter #3: What’s Next?

Hitter #3 is in a different stage of development than Hitters #1 and #2. Those hitters could transition to our next level of training (uHIT Gameday). But Hitter #3 would benefit from breaking through the Accuracy barrier he’s hit in Zone Recognition. From there, we would expect to see gains in his OBP (and possibly his SLG). Right now though, he is at-risk for meeting opposing pitchers that will overmatch him. Going into 2024, we are prioritizing uHIT Custom for his training plan.

Hitter #4

Turning Around Hitter #4’s Season

Hitter #4 stands out among all top-5 users in that he was the top performer in both Pitch and Zone Recognition Training. He finished 2023 +10 XP / Pitch ahead of Hitter #1 on Pitch Recognition at 84 XP / Pitch (he started at just 25 XP / Pitch). And he tied with Hitter #1 on Zone Recognition at 92.5 XP / Pitch (he started at 83.5 XP / Pitch).

From XP / Pitch, we see the biggest change for him has been in Pitch Recognition. His change in Zone Recognition has been minor (and the underlying 79% to 83% Accuracy change reflects that too). In Pitch Recognition, the Accuracy change was the big driver. He went from an Assessment of 50% Accuracy to an end-season average of 78% Accuracy.

Hitter #4: Performance On-field

At first glance, it looked like Hitter #4’s performance got worse. His OPS went down year-over-year. Last year, he hit a 0.701 OPS with 0.371 SLG. This year his overall OPS (across two teams) dropped, hitting 0.644 OPS with 0.333 SLG.

But when we examine closer, we find he actually improved his hitting within season tremendously. Specifically, we see that his first half of season in 2023 weighed down his OPS. His first 85 ABs were at DSL Red, where he hit with a paltry 0.486 OPS and 0.247 SLG. But his second 74 ABs since June 19 were phenomenal: 0.817 OPS and 0.432 SLG. As we know from the analysis of Hitter #2, these two leagues are virtually identical levels of play in the Dominican Summer League. So something was clearly different before and after June 19. One big factor we saw is the amount of progress he made in uHIT Custom.

Deploying uHIT Analysis Service for Hitter #4

Reconciling these year-over-year vs. within-season differences is an example of what we provide additionally for elite-level clients in our uHIT Analysis service (contact to learn more). In particular, we worked with this client’s coaches to take a closer look at what accounted for this under-performance in the first half of 2023. It turned out that there was nothing related to uHIT causing the early-season problems. But to Hitter #4’s credit, he stuck with his uHIT Custom training and netted a within season gain, almost doubling his OPS. 

You can see Hitter #4’s on-field hitting performance excerpted from milb.com here (for a more detailed look, please contact us here):

Hitter #4: What’s Next?

Hitter #4 is in a similar stage of development to Hitters #1 and #2. But he is an even better candidate to transition to our next level of training (uHIT Gameday). He clearly demonstrates the basics for recognizing pitches and zones. Now, we want him to adapt these skills better to game situations. Some hitters, like Hitter #1 and Hitter #2 start doing that transition on their own. But in this case, Hitter #4 could use a slight push to apply those learned skills better to game situations. That’s what uHIT Gameday is made for and that’s why this will be top priority for Hitter #4 in 2024.