Minors to Majors: Problems with Projecting Pitchers

A few days ago, I made my first attempt at trying to determine a pitcher’s value knowing their pitch grades. Since it was published, I have made some adjustments to the pitch grading scale. With the new scale in place, I have been working on comparing grades a pitcher previously received to their actual performance. The results have been extremely disappointing.

In the original article, created a framework to grade individual pitches with an ERA equivalent value (pERA) and a scouting grade on each pitch. While I liked the overall framework, one part really bothered me and I will address the issue first.

The change was to put some consistency in pitch grades, especially with fastballs. The problem was that a pitcher’s fastball is getting graded because of its velocity, but that velocity changes depending on if the pitcher was a starter or reliever. Relievers can really ramp up their velocity when moving to the bullpen.

Because of this bump, I decided to grade all pitches based the pitches starters throw. Now, relief pitchers will have higher grades with some fastball graded out as 100 (normally the maximum grade allowed is 80). Additionally, almost all of the highly-touted pitching prospects are coming into the majors as starters so I needed the scale adjusted for them. I made the change and a new spreadsheet with values going back to 2010 are available here.

The next step was to convert the pitch grades given at various sources back into an overall ERA equivalent score. To do this I weighted the pitcher’s graded pitches and combined the scores. I gave the fastball grade a weight of 55% which is around league average and then weighted the other graded pitches evenly. I should probably find a way to weigh the best breaking ball a bit more, but I will just go with even weighting for now.

I went ahead and gave pitchers grades from over 500 pitchers with scouting grades from Baseball America, MLB.com, and 2080. The initial results are a mess with no correlation. All I could keep thinking was TINSTAAPP (there is no such thing as a pitching prospect). The top of the list of pitchers was basically a list of failed and/or disappointing pitching prospects with some success stories. Here are the top 10 grade pitchers who have already established themselves as major leaguers: Matt Moore, Gerrit Cole, Dylan Bundy, Trevor Bauer, Jacob Turner, Jarrod Parker, Jose Fernandez, Joe Ross, Jordan Lyles, and Martin Perez. Besides Cole and Fernandez, the top pitchers are huge disappointments. Some of the pitchers dealt with injuries which sapped their production (Bundy, Moore, and Parker) while other just sucked (Lyles and Turner). The list doesn’t give a person confidence with current prospects near the top like Julio Urias, Jameson Taillon, Robert Stephenson, Lucas Giolito, Kyle Zimmer, and Anderson Espinoza.

Looking over these top failures, two pieces of information stick out as being out of place. The first is these pitchers’ control grade. Most of them have a value over 50 with Baseball America giving Dylan Bundy grades of 65 in 2014 and 2015. These grades would be equivalent to a 2.0 BB/9 in the majors. It is insane to give a pitcher this grade while they are coming off surgery and haven’t thrown in a year. The control grades are just too ambitious near the top.

The other big issue I have is with the fastball grades. The problem with fastball grades (velocity) is that they don’t correlate decently with results. Let me start with the pitchers who threw 200 four-seam fastballs in 2016. The correlation between the pitch grade based on the fastball velocity and then on the actual results had an r-squared of 0.16.

Additionally, here is an example of two pitchers with differing fastball grades

Yordano Ventura’s fastball:
Average Velocity: 96.1 mph
Grade off Velocity: 70
Swinging Strike Rate: 4.9%
Groundball Rate: 27.5%
Fastball Grade off results: 37

Rick Porcello’s fastball:
Average Velocity: 90.2 mph
Grade off Velocity: 45
Swinging Strike Rate: 11.8%
Groundball Rate: 36.4%
Fastball Grade off results: 76

The results of Porcello’s fastball are quite a bit better than Ventura with over twice the swinging strike rate. Additionally, the minuscule ground ball rate will lead to a high number of easy pop flies and a low BABIP. Just looking off velocity, Ventura’s fastball is elite, but it is straight and easy to read. Porcello’s slower fastball is quite a bit more effective even though it is 6 mph slower.

I know that some interactions exist between the individual pitches causing some other pitches to play up or down. For example, hitters may be sitting on Ventura’s fastball and therefore the results of Ventura’s breaking stuff perform better than expected. The problem is that his fastball is as good as other high-velocity fastballs like the ones Noah Syndergaard throws.

With a ton of question and no answers, I started asking some scouts on how their teams scout pitchers. Here is what I found out.

1. Pre-draft grades are useless for future value.

Most teams have a draft evaluation scale and a separate scale to evaluate players already in the system. Additionally, players graded below Double-A have a mixed grade of hype and some actual production. Once a pitcher is at Double-A, the team really wants to know how they will fit into the organization and they get graded with more scrutiny.

Unless a report in generated in person, like 2080 usually does, prospect publications get their information from these organizational scouts and evaluators. Early published reports on players will have the same inflated early grades especially if a writer talks to an area draft scout. Everyone I talked to doesn’t put much stock on non-first hand reports.

2. Published fastball grades are generally based on just velocity

Tying the fastball grade to velocity makes the grading easier and uniform. A prospect writer can say a pitcher throws X mph and has Y grade. By keeping it this simple, they don’t have to explain any differences in their grades. Every once and a while, a pitcher may get a half grade or “+” grade based on movement, but this rarely happens.

When teams evaluate fastballs, they look for more than just velocity. While velocity is one part of the grade, they will also need to grade a combination of movement and/or command. Movement’s value is easy to understandable but some teams look at fastball command as a proxy for command of other pitches. Also, usually a “top” and “sits at” velocity is recorded with the “sits at” value behind the velocity grade. The final fastball grade can be in the form of combined final grades or grading fastballs into two or three individual grades. Velocity is king, but teams understand it is not the only thing.

3. Control is always average

From talking to many sources, about every touted prospect gets a control grade of 50 even if they are walking every other batter. The only expectation is when the pitcher has two or more plus pitches they may get a 45 grade. This grade inflation is especially true in the lower minors.

Once a pitcher hits Double-A, the team’s almost exclusively move to grading their pitchers off their walk rate. The pitchers are at the point they need to be ready for a jump to the majors. Having a 5.0 BB/9 at Double-A will likely mean the pitcher will have an even higher walk rate in the majors. It seems like Double-A is the real proving ground to see if a pitcher is ready for the majors.

4. Pitchers change

While it may take years of work for a hitter to develop a new swing or plate discipline. A pitcher can change their entire future outlook by changing their position on a baseball. Pitchers are always tinkering with their pitch mix. They may be trying to add more break or velocity to existing pitches. Or they could me adding or dropping a pitch. A non-prospect can come out of nowhere and be a viable major league pitcher (e.g. Corey Kluber).

The other way pitchers change, usually for the worse, is from injuries. Many pitching prospects have had their career ruined from various elbow and shoulder injuries.

5. Pitchers with plus breaking balls in Double-A and Triple-A could be targeted

The scouts I talked to say they look over prospect publications but told me the pitchers to get excited about are the ones in Double-A or higher who have one or more plus breaking balls. They said the fastball grade will usually be inflated, especially if the pitcher was in a Future’s Game. A pitcher may show a velocity-based 80-grade fastball in one inning of work in the game, but it is 60 grade on a daily basis. Instead, if a starting pitcher has made it to the high minors, his overall fastball is average or even above average based on movement and/or command.

The key they say is to then look for above average breaking pitches. These breaking pitches, pair with an average fastball and actual, not projected, decent control are what scouts consider to be legit pitching prospects. All the rest of the pitchers fall into the TINSNAAPP category.


After failing to link up individual pitch grades (which are likely inflated depending on level) to future results, I have a group of pitchers to concentrate on examining to find a link for future results. I have found evaluating pitchers to be frustrating and I can see why other fantasy owners feel the same way. Right now, I have quite a bit of the offseason to hopefully find a better solution. Let me see if the older subset of players can help lead to a better group to target, but I may find nothing. Hopefully, I will have the results later this week.

Jeff, one of the authors of the fantasy baseball guide,The Process, writes for RotoGraphs, The Hardball Times, Rotowire, Baseball America, and BaseballHQ. He has been nominated for two SABR Analytics Research Award for Contemporary Analysis and won it in 2013 in tandem with Bill Petti. He has won three FSWA Awards including on for his MASH series. In his first two seasons in Tout Wars, he's won the H2H league and mixed auction league. Follow him on Twitter @jeffwzimmerman.

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In response to point 5:

Why plus breaking balls, but not changeups? Or are we talking about all offspeed pitches here?