Why Zac Gallen's Free Agency May Have Frustrating Outcome for D-backs

A distinct possibility lies that Gallen will depart from Arizona for a large deal elsewhere, and bring his second-half resurgence with him.

If the D-backs opt not to invest in Gallen — who began to look more and more like an ace in the latter end of 2025 — and he regains his prior form, Arizona may have missed an opportunity to maintain a stabilizing force in their already-thin rotation.

With so little depth at starting pitcher, re-signing Gallen would go a long way to ensuring a large number of innings will be eaten, but it would still be a sizable risk.

A recent article from Bleacher Report's Zachary D. Rymer listed Gallen as a prime candidate to emerge once again as a superstar — but on another club. Here's what Rymer had to say:

"Gallen has had a rough go of things over the last two years, and especially so this season. Though he did recover somewhat in the second half, he still ended up with the eighth-highest ERA among qualified starters.

"Gallen's fastball velocity is holding relatively strong at 93.5 mph, but walks and home runs are much bigger problems for him than they used to be. He also failed to contain left-handed batters in 2025, as they had a career-high .748 OPS against him.

"Further, somebody in the organization probably should have figured out what was wrong with his knuckle-curveball before it went from his greatest strength to his biggest liability."

Will Zac Gallen Prove Diamondbacks Wrong?

With such a poor overall season, it's easy to overlook the fact that Gallen (after going unwanted at the Trade Deadline) appeared to suddenly flip a switch.

Over five starts in the month of August, he threw to a 2.57 ERA. Though he did suffer a pair of poor outings in September, he also posted three Quality Starts, completing the sixth inning or more in nine of 11 starts post-Deadline.

He may not ever regain the form of the 2.54-ERA ace he was in the 2022 season, but with the D-backs' rotation so battered and thinned out, even a mid-range plus starter would be a significant boost.

On top of the fact that Gallen means so much to the organization and manager Torey Lovullo, it would be extremely difficult to see him find his stride again in another city.

The fact is positive regression is likely due for the right-hander. Even if he's no All-Star, it would be difficult to imagine a pitcher with his resume and caliber of stuff pitching at a 4.83-ERA (or worse) rate.

Be warned, D-backs fans: if Gallen goes elsewhere, his results may bring some regret.

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