Pittsburgh Pirates: Top Performing Minor League Hitters Part One

Looking at how the Pittsburgh Pirates prospect hitters in the minor leagues performed in 2018 and who to keep an eye out for in 2019 using z-scores in several offensive categories.

In this month to date, Nick has released our site’s top 30 prospects and earlier in the offseason, I’ve documented composite top 100 rankings based on four major prospect sites.  Today will be the first part of a four-part series, looking at how the Pittsburgh Pirates prospect hitters performed in 2018 to look to see who might be an underrated prospect; the series will go in the order of the really low minors (the three rookie leagues), the low minors (A ball), the upper minors (Double-A and Triple-A), and then ending with a wrap up.

Often times the phrase “you can’t scout the stat line” is thrown around, and it is true, there’s more variables in terms of makeup, a pitcher’s stuff, a hitter’s approach, base running, and fielding, etc.  Teams do try to use a model, with Chris Mitchell’s KATOH being one of the more popular ones, and Kevin Creagh developed the Stat Scout Line.  This analysis isn’t a model, rather a summation of z-scores in different statistics to determine which hitters have performed well compared to other prospects.

Because each level of the minor leagues has different players and the goal is to look at potential prospects (sorry Ryan Lavarnway), setting a maximum age requirement and minimum plate appearance requirement is a must.  Since this is looking at 2018, there will be some players who appear on these lists that are no longer in the organization because of a trade, free agency, or they were released.  For each level among hitters we have the following requirements and the total number of player seasons:

Across each level, the statistics used for how well a prospect has performed will be the following: age, average, on-base, slugging, isolated power (ISO), strikeout rate, and unintentional walk rate.  Strikeout rate will be multiplied by negative one as a lower than average rate is better, and the same goes for age; a prospect younger than average and performing deserves more credit.  The averages for each level are:

Rookie: Dominican League

The Dominican League features a crop of young and talented players that have yet to make their professional debuts on US soil, as these players are still extremely raw.  Often times the top prospects in this league line up with the equivalent of high school sophomores and juniors.  They feature tools, but they’re not yet advanced and often times the biggest drawback is their swing and miss profile.

Yoyner Fajardo is older than the competition at 19 years old, but he did perform with the bat, hitting  .311/.402/.455 with an 11.3 percent walk rate and a 10.9 percent strikeout rate.  He’s a left-handed hitting second baseman, but his age brings down his total-z score, something that is important when trying to find undervalued prospects.

The top performer is Carlos Arroyo, who had a total z of 2.16.  The middle infielder hit .294/.416/.322 in 56 games, with his biggest skillset really being his youth, as the 2018 season was his age 16 season (his birthday is July 11, 2001).  The right-hander didn’t show much power (-0.66 ISO z-score) but showed good discipline in the walk and strikeout rates.

The second best performer in total z-scores, and really the best because of the huge boost Arroyo received with his age z-score, is Juan Pie.  The 17-year-old outfielder hit .258/.382/.421 in 255 plate appearances with a 14.1 percent walk rate and 18.4 percent strikeout rate.  His strikeout rate was around average (just a 0.05 z-score).  The young outfielder seems to be the best prospect of the bunch, by not only this method but traditional scouting.  Fangraphs has Pie as the Pirates 19th top prospect, writing,

“Pie showed a little bit of everything, and we think the upside is that of a 5 hit, 6 power, 5 run/defense type everday right fielder, but it’s still early to be projecting a 5 bat with any certainty given that Pie hasn’t played stateside yet.”

In a youthful crop of players, Pie performed the best among those in the Pirates organization.  To go along with what the scouts see in his tools, Pie could really improve his prospect status with another big 2019 season.  The total-z scores for all eight of the Pirates that meet the criteria in the Dominican League are below, ordered by their total z-score:

Rookie: Gulf Coast League (GCL)

The GCL features a lot of raw players, most recent high school draft picks and first-time stateside players.  There are some players that do stick out for the Pirates, especially a 2018 30th round draft pick in Jack Herman, but he does need to prove himself again this year and against better competition, before he can be viewed as a top 30, or close to, prospect:

Samuel Inoa, a catcher from the Dominican Republic, is interesting, as he showed good power but the walk rate did leave lots to be disappointed.  He is older than the group of players looked at, and 2018 was his first year of pro ball stateside, and he hit .316/.433/.487 in the DSL in 2017.  Fangraphs does note that he might stick as a catcher but do talk about the hit tool.

Ji-Hwan Bae originally signed with the Braves but after their problems in regards to signing international players, Bae signed for $1.25 million with the Pirates.  He didn’t show much with power, being average in slugging and below in ISO, but did make a lot of contact as seen by the strikeout rate z-score.  Bae is most known for his speed, and he went 10/14 in 2018.  His developmental path will be one to watch.

The top performer was Herman, who slashed .340/.435/.489 with a 13.6 percent walk rate and a 14.2 percent strikeout rate.  The outfielder was by far the best of the Pirates performers, and Fangraphs wrote up,

“He’s just 6-foot tall but has a broad-shouldered frame with some room for more mass and there’s already some pop here. His arm is plus.”

There is a lot of risk in Herman, and it’s too soon to make any conclusions, but the corner outfielder did have a loud debut and he’ll need to continue to make noise to be put on the prospect radar, and it’ll be interesting to see if he can continue to hit or if he’ll struggle as Mason Martin did in his second year of pro ball.  The top performers by z-score are: