The Chicago Cubs and Arizona Diamondbacks might be two of baseball's most compatible trade partners as the July 31 deadline approaches. The former has been diligently combing the market for starting pitching help, and the latter has multiple arms that could become available. But if the discussions revolve around Zac Gallen, the National League Central leaders are better off looking elsewhere.
Gallen has been among the hurlers heavily connected to the Cubs ahead of the MLB's cutoff point for outside acquisitions. Coming off consecutive (extremely) quality outings, it's easy to envision fans of the North Siders re-greasing those wheels. However, if Chicago wants to bolster its rotation for a potential World Series run, Arizona's veteran right-hander isn't the answer.
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Cubs should avoid Diamondbacks' Zac Gallen despite trade buzz
Following up a seven-inning, one-run, 10-strikeout start by allowing just one unearned run and tallying another nine punchouts certainly boosts your value if you're Gallen. The Diamondbacks have "one of the most appealing starters on the market" should they decide to be sellers, as MLB Network's Jon Morosi notes. Nonetheless, the Cubs would be wise to invest in a more consistent option.
Despite delivering back-to-back gems, Gallen has been highly volatile in 2025. While he has an extensive, strong résumé, the Cubs have too much at stake to add him. The one-time All-Star's unsteadiness doesn't give Chicago the upgrade on the mound it needs to win a title.
When it's rained for Gallen this year, it's poured. He boasts a 7.50 ERA, 1.667 WHIP and a 6.8 K-rate per nine in his nine losses. Conversely, those numbers contrast starkly with the dazzling 2.22, 0.896 and 11.1 marks across seven wins.
As we've seen in Gallen's most recent two appearances, he still has great stuff. His track record of operating as Arizona's ace over the past three-plus campaigns also shouldn't be overlooked. Yet, this season has been a different story, and the erratic nature of the soon-to-be 30-year-old makes him difficult to trust.
For whatever it's worth, the D-Backs may ultimately save the Cubs from themselves. Arizona adamantly insists they won't be shopping players in the coming weeks and is hanging around in the NL Wild Card race. Assuming neither of those things changes too drastically anytime soon, Chicago must be prepared to pivot.
Note: Stats courtesy of Baseball-Reference.com entering play on July 8, 2025.