Minors to the Majors: Hit Tool Grade Usefulness

Earlier in the offseason, I examined out how reported Hit tool grades compared to actual MLB batting averages. I called the process a “mess” but figured it had some value. When I implemented the formula on MLB.com’s 2017 grades, commenters had the following to say about the projected batting average values:

“… not enough differentiation there in my opinion”
“… adjust your outputs to create more difference..”
“… hoping the table would be more conclusive…”
“…way too tightly grouped to the mean…”
“…it’s better to have no projection than to project everyone to be average…”
“… regressing too much to the mean…”
“… hit tool grades should be ignored…”
“…hit tool is undervalued in prospect analysis…”

I have no issue with the hit values being regressed to the mean. What I do have a problem with is if the hit tool is not measuring the correct factors. I needed to find out if reported hit grades provide any value. The following is a detailed look at how the hit tool is graded and how it fails to predict one simple factor, a hitter’s ability to get hits.

Industry standards

The hit tool is probably the hardest tool to evaluate as Kiley McDaniel explained in a six-part series a couple years back (Part 1 with links other five articles). To start with, here are some Hit tool definitions from various publications.

• 2017 Baseball America Handbook: Hitting ability is as much a skill as it as a tool, but the physical elements – hand-eye coordination, swing mechanics, bat speed – are key factors in the hit grade.

• MLB.com: No definition.

• 2080’s Dave DeFreitas: Bat speed, bat path, exit velo, command of the [strikezone], ease of actions, balance during [the] swing.

• BaseballHQ’s Minor League Baseball Analyst: Measures the player’s ability to hit for batting average and judge the strike zone.

• Kiley McDaniel’s three aspects to the hitting grade.

1. Tools: “This category includes bat speed, raw strength and the basic structure of the swing.”
2. Bat Control: “…ability to change your swing to match the pitch that’s being thrown.”
3. Plate Discipline: “… be able to recognize different types of pitches, get yourself into good counts, lay off the slider in the dirt, etc.”

While most of the prospect grades I have collected have been from MLB.com and Baseball America but they provide the fewest details … if any on grading the Hit tool.

Top Hit grades

With the Hit grade “defined”, the following table contains hitters with a 70 or higher Hit grade (players are only listed once if on multiple rankings).

All these players were expected to produce a .300 or higher batting average with the high Hit grade. Some have. Some haven’t had the opportunity yet. And for those who have failed, here is why.

• Buxton: Contact issues.
• Ackley: Not enough power behind the contact, low BABIP (.279 for career).
• Hosmer: Not a complete failure but swings out of the zone too much leading to weak contact.
• Montero: No plate discipline.
• Chisenhall: Swings too much out of the zone.
• Castellanos: Swings at nonstrikes and has contact issues.
• Odor: Swings at everything.
• Drew: He may have disappointed but performed as expected until falling apart after the 2010 season.

The one common denominator holding most of these guys back from reaching a high batting average is plate discipline with a couple having contact issues (from probably swinging at pitches out of the zone).

With some idea of what the Hit grades are missing, I will move onto the common traits of good MLB hitters.

Determining MLB hit tool

This process is fairly straight forward, find the features of good MLB hitters as a reference to use with prospects. First, here are the top and bottom 10 hitters since 2008 ranked by Contact% (min 2000 PA). The ability to make contact is one of the main traits included in the Hit tool.

The biggest take away from the above list is the division of slap (high contact) and power (low contact) hitters.

The next step is the part of this procedure I have the least confidence in. How to split the power aspect between the power grade and the hit tool. Sadly, I agree with Kiley when he says the Hit tool must contain “…bat speed, raw strength and the basic structure of the swing.” Some line drive power aspect belongs to the hit tool, to get hits, but separating it from the Power grade is where I don’t feel perfectly comfortable.

I have an answer but I may easily change my mind in the future. I went with: All hits in play minus infield hits (Speed component) divided by balls in play minus infield hits. A modified BABIP. The extra base hit components (~ISO) will be the Power grade. Basically, can the batter hit the ball hard enough to get on base? It’s probably not perfect but it will allow this study to continue. Feel free to insert your own opinion on this matter. Here the top and bottom players for this metric.

The top table contains better hitters but some lack plate discipline. As we saw with the failed prospects, most of these guys were swinging at pitches out of the strike zone. Here are the top and bottom hitters who chased too many pitches.

Having a great strike zone understanding and not swinging at pitches out of the zone doesn’t make a hitter good. But on the other end of the spectrum, not being able to identify pitches out of the strike zone can limit a hitter’s potential.

Now I get to the hardest step, how to combine the three sort-of-related factors into a single hit factor. I messed around with different combinations and came up with the following simple equation and subsequent leaderboard:

2 * Hit Rate – O-Swing% + Contact% = MLB Hit Tool

Looking over the list as an idiot test, three names may stick out as out of place, Scutaro, Carroll, and Guerrero. With Carroll and Scutaro, people must remember this tool is just for hitting and getting on base (~.350 OBP for the pair’s career). They mainly had gap power which puts them above the like of Denard Span who uses his Speed to get on. As for Guerrero, he was at the end of this career and was really struggling at the plate with less power.

Now, I have a good idea of the components for a good MLB hitter. I am ready to move onto the final step, comparing the three above components to the hit grades of recently promoted prospects to see if they match.

Comparing Hit grades to results

For this section, I took 25 prospects (almost equally distributed between Baseball America and MLB.com) from the past three seasons who debuted and had 200 plate appearances. Here is how their Hit Grade compared to their results.

I expected the correlation to be low because the grades are at five point intervals, but not this low. At least the Contact% and O-swing% are positive. The Hit% is a negative correlation. Yep, the higher the Hit tool, the fewer times a prospect gets a hit when he puts it in play. This is an issue.

Now, here is the combined equation compared to the Hit grade:

An r-squared of 0.01? A negative correlation? Basically, the Hit tool is a useless component to determine hitter value as it’s currently being distributed. It shows a small ability for making contact and plate discipline but just barely. Additionally, it misses on a hitter’s ability to generate hits.

I think it’s time to see if a better solution exists in correctly predicting the Hit tool. I have some ideas but those will have to wait for a future article. Until then, happy prospecting.