Zac Gallen's 2024 Projection is Somewhat Concerning

The projections expect a significant drop-off for the D-backs ace for the 2024 season after a slow finish to 2023.

This article is part of a series taking a look into individual Diamondbacks player projections as we head into the 2024 Spring Training. The projections presented are a composite of the rate (percentage) stats from Steamer and ZiPS as published on Fangraphs. The playing time projection is our own and is based on the current roster as of the time of this writing. Further roster changes will impact the playing time and thus the WAR projection, but not the rate or percentage statistics presented.

This projection will go over Diamondbacks ace Zac Gallen. Gallen finished third in the National League Cy Young Award race in 2023, his second consecutive Top 5 finish. With him taking his game to the next level, expectations are high for their Opening Day starter to deliver another strong performance in 2024.

Projection

Zac Gallen 2024 Projections / Jack Sommers

The projections expect Gallen to be the workhorse at the top of the D-backs rotation, totaling 185 innings and a 3.69 ERA in 30 starts. It would be the third consecutive season of 30+ starts, following 31 in 2022 and 34 plus six postseason starts in 2023. Despite the projections having Gallen posting above-average strikeout (23.6%) and walk rates (6.8%), it predicts his strikeout rate to drop to a career-low by more than 2%. That in itself is a concerning part, as a drop-off in strikeouts is usually the first sign of decline. That will be something for the D-backs to watch in 2024. With a projected 3.69 ERA and a 3.85 FIP, it's unlikely Gallen will continue his run of Top 5 Cy Young finishes without outperforming them.

Why Gallen Can Outperform this Projection

Just being healthy all season, Gallen is likely to pitch more than 185 innings. Depending on the D-backs postseason aspirations, a healthy Gallen will make 33-34 starts and finish close to 200 innings. His strikeout rate, while slowly declining year-to-year, has never finished below 26% in any full season of his career. On days he has at least three of his four main pitches working, he can rack up a pretty high strikeout total. Additionally at the same time, Gallen's walk rate has improved faster than his strikeout rate has declined. Entering his Age 28 season, Gallen is still on a short list of pitchers that are in contention for the National League Cy Young. 

With four above-average to plus pitches, Gallen at his best is very daunting for an opposing lineup despite average velocity. After establishing his fastball in the strike zone, he uses his curveball and changeup for swings and misses. One other particular note is Gallen does not fall into a particular pattern for usage, always attempting to stay ahead of his opponents. That is both his biggest strength and weakness, as sometimes he can get caught up in the trap of overthinking instead of executing pitches.

Why Gallen Might Underperform this Projection

Gallen's second half of 2023 proves as a cautionary tale, as his quality of contact and home run rate took a turn for the worse. Additionally the innings jump from 184 in 2022 to 243 2/3 in 2023 isn't something to overlook either. The D-backs have not had a starter pitch 240 combined innings, regular and postseason, since Brandon Webb in 2007. That workload could show up in his velocity, which has alternated between 93-94 MPH for most of his career, or in the form of injuries. The D-backs will need to be cognizant of Gallen's workload entering the 2024 season as a result. 

One other thing to note is Gallen's constantly declining strikeout rate. Part of that is due to a conscious decision to attack the strike zone early in the count, resulting in more balls in play and fewer strikeouts and walks in his profile. Coupled with his quality of contact getting much worse in the second half of 2023, we could be reaching the point where Gallen has either peaked or is about to reach the end of his peak. He's shown the ability to reinvent himself on the fly, so it's hardly a career-ending concern.

Summary

Like with Gallen, the projection is a bit disappointing for someone many expect to be in the mix for the Cy Young Award. He'll need to show that the second half of 2023 was a blip instead of a sign of things to come. If he's able to stay healthy considering the big increase in workload last season and provide another 200 inning season, the D-backs should be in good shape to compete for the 2024 season.