Arizona Diamondbacks starting pitcher Zac Gallen (23) delivers during the second inning against the San Diego Padres at Petco Park on July 7. Denis Poroy-Imagn Images

MLB Insider Plants Seed of Blockbuster Trade Between Seattle Mariners and D-backs

Originally posted on Seattle Mariners on SI
By Brady Farkas | Last updated Jul 8, 2025 6:30 PM ET

The Seattle Mariners have been linked to the Arizona Diamondbacks as a possible trade partner for weeks.

However, those conversations have generally centered on third baseman Eugenio Suarez and first baseman Josh Naylor, both of whom would be solid additions to the Seattle lineup.

But could the M's actually get involved in conversations for another member of Arizona's roster? While not an official report, MLB Insider Jon Morosi of the MLB Network did put this note on social media earlier on Tuesday:

Zac Gallen has put together his 2nd consecutive strong outing.

6 innings, 0 earned runs, 9 strikeouts, 1 walk

If the DBacks are deadline sellers, they have one of the most appealing starters on the market.

The Mariners and DBacks are frequent trade partners, with 5 deals involving major league players since Jerry Dipoto arrived in Seattle.

If the M’s need an arm, this is one scenario that could develop closer to the deadline.

The Mariners and DBacks are frequent trade partners, with 5 deals involving major league players since Jerry Dipoto arrived in Seattle.

If the M’s need an arm, this is one scenario that could develop closer to the deadline. @MLBNetwork @SeattleSports https://t.co/xGxZ8GIBVI
— Jon Morosi (@jonmorosi) July 8, 2025

Now, there's a few things going on here.

First, Gallen will be one of the most coveted pitchers at the trade deadline, so the price to acquire him could be high. The Mariners have nine Top-100 prospects (according to MLB Pipeline), but do they want to use them on a rental pitcher who has gone 7-9 with a 5.15 ERA this season?

Furthermore, Gallen was making $13.5 million this season, which means he'll have about $6 million or so remaining by the deadline. The Mariners have said they are willing to add payroll, but do they want to do that on a non-offensive addition?

Then, there's also the question of whether or not the Mariners actually need to acquire a starter. George Kirby, Logan Gilbert, Bryan Woo and Luis Castillo are healthy right now - and Bryce Miller could be back by August. If he's not, Emerson Hancock and Logan Evans have filled in admirably.

However, given that Miller is not a certainly, and that Evans may bump up against innings limits, the idea of bringing in a starter certainly isn't out of nowhere. The trade deadline is July 31.

The Mariners enter play on Tuesday at 48-42 and in possession of the third and final wild card spot in the American League. They'll play the Yankees at 4:05 p.m. PT.

This article first appeared on Seattle Mariners on SI and was syndicated with permission.

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