Prospect highlight: Paul Skenes

The debate on Paul Skenes’ fastball

A critique on the fastball shape argument and why Skenes’ subpar four-seam shape should not matter

By Aidan Treu

 

Opinions on Paul Skenes’ fastball stem from two schools of thought. The first is that his subpar fastball shape could lead to trouble at the highest level. The second is he throws too hard for it to matter.

For those unfamiliar, a fastball with bad shape can be referred to as a dead zone fastball. In simple terms, this means the pitch moves in a way that is easy for batters to predict. These pitches have no type of movement, whether vertical or horizontal, that makes them stand out from the fastball the batter is expecting.

The first point in favor of Skenes is velocity is generally slightly more effective at getting whiffs than a decrease in fastball drop.

Typically speaking, the less a pitcher can get their fastball to drop, the more ride it will have through the zone and the more it will almost appear to rise to a hitter.

 

From the start of 2020 to the end of the 2023 season, increased fastball velocity has a slightly higher correlation with whiff rate.

In a vacuum, this tells us two things. For one, elite velocity probably matters slightly more than vertical break. For two, pitchers can overcome a lack of beneficial movement with their velocity. Jesus Luzardo is another pitcher who has been tabbed as having a dead-zone fastball, but he is still able to generate a strong whiff rate.

These numbers hold true for Skenes in his small minor-league sample size. While his fastball drop, or lack thereof, is not particularly impressive, his fastball is generating plenty of swing-and-miss. This is shown well in a tweet by Thomas Nestico: https://x.com/TJStats/status/1774154240270770346?s=20

His tweet brings up another important topic. Bad four-seam fastball shape makes it easier for batters to predict where the ball is going. It is much easier to do so when you have a good idea of what pitch the pitcher is going to throw. Skenes' full arsenal is going to do the work of negating that.

Major league fastballs usually take less than half of a second to reach the plate (even less for Skenes' 100+ mph pitches). With that little time, it is much easier to connect with a predictable fastball path when you can sit on the fastball. Batters can do that against some high-velocity pitchers. Batters cannot do that against Skenes.

There is a very legitimate argument that Skenes’ fastball is not even his best pitch as he also boasts a wipeout slider in the upper 80s. He is also working on a changeup that has graded well on stuff+ models, but we have not seen very much of it because he has not needed a third offering to this point.

Regardless of what his best pitch is or how good his changeup will be, his ability to keep batters confused will give them even less time to guess, further decreasing the importance of his fastball shape.

Pitchers with elite velocity and breaking stuff can get into trouble allowing home runs, even if they have not been plagued by the long ball until they reach the highest level.

These types of pitchers are usually good at limiting hits. As a result, rallies against them may have to come from the instant offense that home runs provide.

With their elite velocity often comes the good fastball ride through the zone. It may help these toolsy pitchers miss more bats, but home runs are predicated on getting under the ball at the right angle. Less fastball drop makes it easier to get under the ball.

Skenes’ fastball may be easier to make contact with compared to an otherwise identical fastball with a different vertical break, but it may also prove to be more effective at preventing the long ball. If true, batters will have to score by stringing singles and walks together against 100 mph fastballs and 90 mph sliders.

No one has been able to consistently do that against Skenes since his transfer to Louisiana State University, as evidenced by his 0.75 WHIP while there.

A big difference between Skenes and the stereotypical hard-thrower with a good breaking ball is his command.

He clearly has a pension for targeting the high and away portion of the zone for strikeouts and is able to do it repeatedly. He also changes where he stands on the rubber depending on the handedness of the hitter and is still able to repeat his delivery. Both of those things point toward a pitcher who will be able to avoid mistake pitches.

There are countless examples of baseball prospects succeeding all the way through college and the minor leagues but not figuring it out after reaching the Majors. There is no way for anyone to be certain whether that will happen to Skenes.

There is, however, reason to believe one of the biggest critiques of his game will be far less of an issue than critics make it out to be.