The D-backs’ Deadline Dilemma: Trade Their Ace or Hold On?

Zac Gallen has been the Diamondbacks’ ace since his second-half breakout in 2022. Now, just three years later, Arizona faces a dilemma as Gallen approaches free agency after the season: trade him for a return or hold onto him and extend a qualifying offer.

Both options carry merit for the club. On the one hand, it would be good to salvage a return for their ace in a year they’re nowhere close to contention. However, his overall track record makes him a strong candidate to receive a qualifying offer, which should be estimated to be worth $21-22 million this offseason. Should Gallen accept, that means he’ll anchor the rotation again in 2026. If he doesn’t and he walks for a contract worth more than $50 million, it will net the D-backs a top-30 pick in next year’s draft.

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With the team exiting the All-Star break at 47-50 and 5.5 games out of a playoff spot, general manager Mike Hazen has to make some tough decisions regarding the club. Gallen is one of four impending free agents, along with Josh Naylor, Eugenio Suárez, and Merrill Kelly, who should draw some interest at the trade deadline.

However, this decision isn’t so cut and dry for Hazen and the baseball operations department. There are several factors that they will have to consider before pulling the trigger on a deal. The biggest one is the type of return that other teams are discussing and weighing against the potential value of one more year of Gallen in the rotation or the value the draft pick brings.

The same process also applies to Naylor, Suárez, and Kelly. If the offers don’t measure up, expect Hazen to change the subject and hang up the phone.

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There remains clear value in not closing the door to a potential 2026 return for both Gallen and Kelly. The starting rotation has been decimated by injuries, with three pitchers likely to open the 2026 season on the 60-day injured list. The team is pursuing young pitching at the trade deadline, so they’ll need veteran mentors.

Kelly seems the more likely of the two to re-sign, but it’s also possible Gallen sees the merit in a one-year offer and tries to rebuild his free agent value for the next winter. That was the same approach that Tigers pitcher Jack Flaherty took after a dismal 2023. He accepted a one-year offer from the Tigers, pitched well in 2024, then earned a more lucrative deal. However, it may not serve as a good data point for Gallen, as he settled for a two-year deal after a cold market.

It will be interesting to see how the process plays out over the next two weeks. If they do indeed trade Gallen, they’ll need to fill up their rotation by acquiring young starting pitching at the deadline.

We’re going to look at potential trade comparisons for Zac Gallen. Looking at his current situation, these are potential qualifying offer candidates that the team elected to trade, dating back to 2022.

• RHP Lucas Giolito (CWS, 2023)
• LHP Jordan Montgomery (STL, 2023)
• RHP Jack Flaherty (DET, 2024)

The commonality of the three pitchers was that they were in their Age 30 or younger season. Both Giolito and Flaherty were in their Age 28 season, while Montgomery was in his Age 30 season and Gallen 29. It’s worth noting that Gallen doesn’t hit 30 until August 3rd, which is also my birthday (I turn 32).

Comparing their walk year at the deadline, these are how the four pitchers stack up.

Compared to the other three pitchers, Gallen’s contract year is much worse. That’s a result of a 5.40 ERA and inconsistent results with his curveball. However, he’s shown to be equally as effective at eating innings and entered the season with bigger expectations. The decreased effectiveness in 2025 will likely limit the potential return in a deal.

At the same time, the D-backs are more than justified in setting a high price in a potential deal. Gallen has pitched the most innings of the group and stacks up fairly well across the board in the other metrics.

The potential return Arizona should get for Gallen should be in the ballpark of what the other three pitchers got when looking at a three-year track record.

Montgomery, who was traded along with reliever Chris Stratton, netted left-handed reliever John King plus Double-A prospects Thomas Saggese and Tekoah Roby. Giolito, who came with reliever Reynaldo Lopez, brought back Edgar Quero and Ky Bush. Jack Flaherty turned into infielder Trey Sweeney and catcher Thayron Liranzo.

Based on the previous data points, Gallen should be able to fetch a mid-tier prospect that’s close to major league ready and a potential high-impact prospect in the lower minors. The latter prospect is going to be very similar in value to the draft pick they’d likely receive if he walks in free agency after declining a qualifying offer.

If Hazen sweetens the package by adding Suárez or Naylor, it could potentially increase the impact of a return and get the young pitching they’re searching for at the deadline. The Yankees and Brewers line up well as potential trade partners in a Gallen+Suárez package, especially if they can target Cam Schlitter or Logan Henderson. Another option would be a Gallen+Naylor package to the Houston Astros for Miguel Ullola or A.J. Blublaugh.