Why Zac Gallen Could Return to Ace Form in 2026

Arizona Diamondbacks right-hander Zac Gallen had the worst season of his major league career in 2025. He's determined to not let that happen again.

Last year, his 4.83 ERA over 192 innings was over half a run worse than his previous high of 4.30 in 2021. His 21.5% strikeout rate and 31 homers surrendered were also career worsts, by wide margins.

Those numbers are part of what contributed to a relatively stagnant free agent market for the former All-Star Game starter this offseason. After turning down a qualifying offer, he ended up back in Arizona on an equivalent one-year deal — this time with something to prove.

"I've always kind of bet on myself," he said. "I think I felt like I owed it to myself, owed to my family, even owed it to the organization, the fans here, [to] come back, have a good year and kind of prove my worth again and kind of get that little added extra motivation."

Gallen certainly is a pitcher who has thrown better with a chip on his shoulder. 2025 may be the most prime example of that. Though he was shopped at the trade deadline, no team was willing to acquire him for the price Arizona set. After the deadline passed, Gallen threw to a 3.32 ERA over 11 starts to end the year.

And that may very well be the version of Gallen taking the mound in 2026 — but not just because of his mindset.

Why Arizona Diamondbacks' Zac Gallen Might Bounce Back

Ever the self-proclaimed "tinkerer" when it comes to his stuff and mechanics, Gallen dove into the jump from first-half 2025 to the second half.

"I talk about delivery and how I move pretty frequently. I think just I had, first half, kind of got into some really bad habits of just how I was moving, and it was making shapes and command really inconsistent.

"I think you what you saw in the second half was me starting to clean up those movement patterns and shapes were getting back to what I was used to. Pitches were breaking how I wanted them to. I knew where to start them.

"It's like anyone that plays golf knows like lines up to your eye, things like that. So for me, I think that's what you saw in the second half," Gallen said.

Still, the right-hander knew there was "work to be done" this offseason. He said he made tweaks to his workout regimen, and likes where his movement and shapes are at heading into spring training.

"I'm moving a little bit more efficiently. I think we've gotten the shapes back to where my eye is trained to see and where my arm is used to the ball coming out and the shapes going how we want to. ... so I feel like we're in a good spot," he said.

Why Arizona Diamondbacks' Zac Gallen Might Bounce Back

Arizona Diamondbacks Latest News