2025 Fantasy Baseball: Zac Gallen Profile, Preview, Predictions

After a workhorse season in 2023 due to pitching in the postseason, Zac Gallen lost his command last year while missing a chunk of the season with a hamstring issue. He has 31 wins over the past two seasons. With two sub-3.00 ERAs on his career resume, Gallen has the tools to be a value ace in 2025.

Changeups Gone Wild

When Zac Gallen's Accidental Cut-Changeup (7" of cut) Fooled everyone...

Including Zac. 🤣 pic.twitter.com/DX5PROuDkB
— Rob Friedman (@PitchingNinja) January 16, 2025

SP – Zac Gallen, ARI (ADP – 118.5)

2025 Zac Gallen Pitching Stats Profile | Shawn Childs

The difference between Gallen’s success in 2023 (17-9 with a 3.47 ERA, 1.119 WHIP, and 220 strikeouts over 210.0 innings) was six starts and 62 innings. Unfortunately, even with a repeated strikeout rate (9.5), he finished 74 K’s shy of his previous year due to averaging only 5.3 innings per start compared to 6.2 in 2023. Gallen walked more batters (3.3 per nine – 2.0 in 2023) with a minimal change in batting average against (.237).

Over his first 10 games in 2024, he went 5-4 with a 3.12 ERA, 1.127 WHIP, and 60 strikeouts over 57.2 innings. A hamstring cost him a month of the season. Gallen looked sharp in his return from the IL (six shutout innings with two baserunners and seven strikeouts). The Diamondbacks pitched him past the sixth inning only once over his final 16 starts. His ERA (4.27) and WHIP (1.411) were liabilities over 84.1 innings due to an increase in walks (38).

His average fastball (93.8) aligned with his previous three seasons. Gallen started to ditch his cutter (.200 BAA) while tossing more curveballs (.147 BAA) and sliders (.342 BAA). He continues to feature a changeup (.267 BAA) as his third usage pitch (14.1%). Batters banged around his four-seamer (.278 with 18 doubles, two triples, and seven home runs over 241 at-bats).

Fantasy Outlook: His stats were close over the past two seasons other than the length of his season due to his injury. On his pitch mix side, Gallen had a sharp decline in his four-seamer (.237 BAA), changeup (.201 BAA), and slider (.225 BAA) from his 2023 season. In addition, home plate was more challenging to find. With no reported arm injury, let’s hope his struggles were mechanical or a possible result of a heavy workload in 2023 (243.2 innings).

After a down season in 2021 with command issues, Gallen had a rebound season the following year. Based on this, I expect his arm to be more valuable to fantasy teams in 2025. His 200-strikeout potential is intact if he makes 32 starts, but he has to throw more strikes and regain his lost arsenal to push higher up the pitcher ranking.

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