Analyzing the 2018 MLB Draft Class:

Who has Been the Best College Pitcher Drafted?

Introduction

After completion of their first full season of pro ball, we can begin to gauge on which pitchers are performing at a high level. We can also begin to see which pitchers are either providing high value to their team by outpreforming their draft slot or, which pitchers are underperforming with respect to their draft slot. This can be easily done through a combination of the use of the “eye-test” and statistical evaluation. Certain statistics hold greater value in measuring the true performance of a pitcher than others and give a more accurate evaluation on assessing the pitcher’s current results and projected results. With the modern era of MLB being head-over-heels with analytics and player development, much more pressure is being put on prospects to produce results. Results that either show early success or results that show that player development can take over, and take the player to the next level. With that stated, I wanted to answer the following question. Which college pitcher, amongst the first 15 selected, in the 2018 MLB draft, has performed the best?

*This sample was chosen from the first 15 college pitchers selected in a draft as they are usually deemed to end up “the best” in regards to pro success. So I wanted to see which players were providing the most value to their organization. Additionally, I wanted to provide my own personal evaluations on the players and give my evaluator/scout take on which pitchers I think will ultimately experience the most success in the big leagues.

Table Background: An analysis of the table would show how well a pitcher is at striking hitters out, throwing strikes, and limiting runs which are three vital components for a pitcher to control. The modern day game of MLB preaches strikeout rates, limiting HRs, and filling up the strike zone and these are the driving traits in which pitches are evaluated upon and need to be evaluated on. Also, with collegiate pitchers being older than HS pitchers when entering pro ball, they are expected to perform at a higher level when entering pro ball as they are closer to the big leagues. Hence, why it is inaccurate to compare a highschooler’s first season of pro ball vs a college pitcher’s first season of proball. The following is an accumulation of each pitcher’s career stats so far in the minor leagues.

• All numbers were either calculated or gathered from Baseball Reference of Fangraphs. FIP was calculated with a cFIP of 3.216 in “R”.
• The table descends in order from the first college pitcher selected in the 2018 MLB Draft, (Mize), to the fifteenth (Gray).

Why the Statistics Were Selected:

IP: Measures volume and sample size of accumulated statistics.

Innings Pitched

K/9: Ability to strikeout hitters.

Strikeouts per 9 innings

BB/9: Ability to command the zone and throw strikes.

Walks per 9 innings

K/BB: How many hitters are they expected to strikeout for every free base they allow.

Strikeout to walk ratio

K%: How often do hitters strike out against the pitcher and his stuff.

Strikeout percentage

FIP: Pitcher’s three true outcomes into an earned run average-like number

Fielding Independent Pitching

ERA: Shows an average of how many runs are allowed when they take the mound.

Earned Run Average

HR/9: Ability to keep the ball in the ballpark in the launch angle area.

Home Runs allowed per 9 innings

GB%: Ability to keep the ball on the ground and generate double plays

Percentage of balls in play that are ground balls

BABIP: A hitter’s ability to get a hit for when they put the ball in play off the pitcher.

Batting Average on Balls In Play

Analysis

Strikeouts: The K/9 v.s BB/9 graph can explicitly show which pitchers are power pitchers, strike-throwers, and command issue pitchers. This is due to the relationship between K/9 and BB/9. The association is an easy reference to project pitchers for their prospective roles at the major league level (e.g., front line starter, back end starter, power reliever, swingman, etc.). In this case, with Nick Sandlin drafted as a reliever, this supports the fact that he is a power reliever and someone who could pitch in the 7th inning or later with his higher BB/9. Sandlin’s performance in the minors so far has asserted he will be a power reliever in the big leagues. The pitchers with the best combination of the statistics, as mentioned earlier, are Casey Mize, Logan Gilbert, Daniel Lynch, Kris Bubic, and Josiah Gray. They profile as guys who are capable of pitching towards the front of the rotation based on their K/9, BB/9, K/BB, and K%. However, while Shane McClanahan has shown the ability to have a high K/9 and K%, he has a high walk rate at 3.24. Such a combination of statistics raises questions into whether or not a pitcher can be a starter or a reliever. In McClanahan’s case, he can be a 2–3 starter at best or be an Andrew Miller-esque power reliever.

On the other end, based on K/9, BB/9, K/BB, and K%, Sean Hjelle, Jonathan Bowlan, and Tim Cate profile as backend starters due to their lack of ability to strike hitters out at an above-average rate. Additionally, Hjelle and Bowlan have shown the ability to throw strikes form their low BB/9 rates so they can profile as inning eaters. However, Cate needs to refine his control to reach his ceiling of a #3 or #4 starter as his command is holding him back from his potential. Brady Singer, Ryan Rolison, and Jackson Kowar have all individually came into pro ball with their standards and expectations. Singer was rated as the 2nd best college pitcher coming into the draft and labeled as a future ace. His early performance has indicated that he is indeed an elite pitching prospect, but based on the numbers, he is profiling as a safe #2 starter prospect with a #1 ceiling. Rolison, is actually exposed by his numbers as they indicate he is a more backend starter. However, a deeper dive in his pitching profile has shown that he is not a power pitcher, but a ground ball pitcher, In addition to this, he has been massively hurt by the long ball in his minor league career to date. All in all, weighing his performance, pedigree, and the idea that home runs will continue to increase in MLB, Rolison is molding to that of a #4 starter. Kowar has been very consistent and steady to this date and has shown that he can be a reliable big-league pitcher in that of a #2 or #3 profile between his K/9, BB/9, K/BB, and K%. Michael Grove has early on shown strikeout stuff but, due to him being a starter and his small sample size of 51.2 innings, it’s too early to project his place in MLB. But, a nonstatistical consideration is that he is indeed in the Dodgers player development system, so he is someone to keep an eye on this upcoming season. Lastly, Griffin Roberts has yet to gain control over his above-average breaking ball and fastball into consistent quality strikes, as shown by his K/9, BB/9, K/BB, and K%; supporting his reliever profile.

Run Prevention: More goes into evaluating the pitcher’s success besides K/9, BB/9, K/BB, and K%. FIP is a very accurate portrayal of a player’s run prevention ability, and this is the defining statistic that separates aces from the pack. With Casey Mize, Logan Gilbert, Daniel Lynch, Kris Bubic, and Josiah Gray mentioned as future frontend rotation guys based on their strikeout and walk numbers, and their FIP will show what type of pitcher they are. An analysis of their FIP numbers validates that the pitchers above are guys capable of pitching in the number 1–2 spots in an MLB rotation. Additionally, the above graph shows how accurate a player’s FIP and ERA are in measuring their run prevention by showing the correlation between the two. This display makes it easy to see which pitchers are undervalued or overvalued based upon their ERA and FIP measures; with FIP giving a more accurate measurement of run prevention. This validates that runs are hard to come by when facing Mize, GIlbert, Lynch, Bubic, or Gray.

Percentiles: I chose to display each player’s overall performance through percentiles concerning one another’s performance. The percentiles also show which teams have drawn the most value from their players and selections. Many arguments can be made on players’ value and ability through the display of percentiles.

First of all, Josiah Gray has been amazing to the date and has outperformed everyone drafted in front of him except Logan Gilbert. He is easily the top steal so far amongst the college pitchers selected in the 2018 Draft and will bring great value to the Dodgers in the future. Leading into my next belief as supported analytically; Logan Gilbert is a better pitching prospect than Casey Mize. Gilbert bests Mize in every one of the recorded statistics except for HR/9 and BABIP. Moreover, Gilbert’s HR/9 is still above average at 0.5, and the BABIP was shown to display a pitcher’s luck. It’s known that an average BABIP is .300 and BABIPs that are significantly lower than .300 show increased luck while those significantly above .300 show an unlucky factor in a pitcher’s performance. Mize’s BABIP is .265, while Gilbert has a BABIP of .285. Therefore, over time and when pitching in the big leagues, each pitcher can expect a BABIP regression with an effect of that being a higher FIP. Thus, Gilbert is beating Mize in all categories even though Mize has numbers skewed by luck. Gilbert’s K/9, K%, and FIP are significantly better than those of Mize and support that Gilbert has been the better overall pitcher. The only thing holding Gilbert back from being recognized on the same prospect tier as Mize is that Mize was a #1 overall pick, and such players are viewed in a higher light than others (deservedly so). However, this doesn’t take away from the fact Logan Gilbert has outperformed a first overall pick and is an ace in the making.

Value: The last and final table is meant to showcase the value a pitcher has provided in reference to their draft position and performance. Right off the bat, as mentioned earlier, Josiah Gray has provided value that advocates for him to have been the second college pitcher drafted and that of a player in the first half of the first round. In addition to Logan Gilbert being the top-performing collegiate pitcher, Casey Mize has been outperformed by two other pitchers in Gray and Kris Bubic. Nevertheless, there is a clear distinction in “levels” of a pitcher’s performance and prospective MLB role. With the top five performing pitchers representing guys who will pitch in the front half of a rotation. Ryan Rolison has not warranted the full value of being a first-round pick to date and is the biggest underperformer in the 2018 Draft relative to his draft position.

Conclusion

The above displays of data assist in answering the question of “Who has been the best college pitcher drafted?”. For future projections, it would be beneficial to find the above MILB numbers from current MLB pitchers and compare them to a pitching prospect to find trends in types of pitchers and know what kind of pitcher a team is getting. Lastly, raw data and sometimes even the most basic statistics display the reality of a pitcher’s ability in the best way possible.