While Moniak still holds plenty of promise, he’ll need to have a notable rebound in 2018 in order to once again be seen as one of the top prospects in the game. After being ranked 17th on Baseball America’s annual list of the top-100 prospects in baseball last year, Moniak was left off of the 2018 list entirely when it came out last month. Given that 2017 was his first full season in professional baseball, it’s certainly far too early to assume the worst about what this might hold for his major league career. That said, such a large drop-off is still at least somewhat concerning and deserves an explanation beyond just assuming that he’s still adjusting.
The wealth of advanced statistics we have for major leaguers aren’t readily available for minor league players, especially those who haven’t made it past single-A. That said, a closer look at some of Moniak’s stats from last year do give us more insight into his decline.
First let’s look at his lack of raw power. While power is one of the last things to develop, his slugging percentage dropped off 68 points from 2016 to last year (.409 to .341), and his isolated power (ISO) also took a notable hit. Calculating his extra base percentage by subtracting batting average from slugging, his 2017 ISO was just .105, down from an already low .125 in 2016.
Moniak also experienced drops in his secondary average (SecA) and batting average on balls in play (BABIP), going from .222 to .174 and .350 to .297, respectively. SecA seeks to analyze how many bases a player took independent of his batting average, while BABIP looks at batting average in instances where the batter ended up making contact. In both instances, it’s clear that his offensive performance suffered in part from a lack of an ability to take bases when given the opportunity. His double rate fell (1/16 PA in 2016, 1/23 PA in 2017), and his strikeout rate rose (1/5.5 PA or 18% in 2016, 1/4.6 PA or 21.4% in 2017).
It’s true that Moniak was never projected to be a huge slugger that could hit 40-50 home runs in a season, but this steep decline in power is still very much noteworthy. He has in fact been touted as a five-tool player with at least 20-plus home run power, so seeing him struggle to come close to even that has definitely raised a few eyebrows.
While it makes sense that some of Moniak’s average-based stats would take a hit in his first full season, it was strange to see that many of his whole-number stats didn’t increase quite as much as one might expect. The steals in particular were surprising, as he only increased his total by one, from 10 in 2016 to 11 last year. More concerning, his success percentage fell (71% in 2016, 61% in 2017).
In many respsects, it’s clear that Moniak still has a lot of growing to do as a professional baseball player. That said, we’re also not talking about a fourth-year major leaguer who has yet to capture any of the hype he had as a prospect. We’re talking about a player who only just completed his first professional season and would still have a lot of developing to do even if that season had been a resounding success. This is why players usually take several years to come through the system while making their way to the big leagues. It’s still far too early to make any definitive statements about what his 2017 season may or may not say about his prospective major league career.
When all is said and done, being left off Baseball America’s top 100 list of prospects could even end up being a good thing for Moniak. Looking back to J.P. Crawford last year, he was motivated to up his game when he saw that his lackluster performance early in the year caused him to be knocked down on many midseason prospect rankings. Crawford took those criticisms to heart and proceeded to go on a tear for the rest of his minor league season, which would ultimately result in his call to the Phillies. There’s certainly no guarantee that the same thing will happen to Moniak, but it will certainly be interesting to see the Phils’ No. 1 pick continue to develop in 2018.