And we're off: The first big move of the 2025 trade deadline arrived on Thursday night, as the Seattle Mariners acquired first baseman Josh Naylor from the Arizona Diamondbacks in exchange for Minor League pitchers Brandyn Garcia and Ashton Izzi. ESPN's Jeff Passan was the first to break the news.
Left-hander Brandyn Garcia and right-hander Ashton Izzi are headed back to the Arizona Diamondbacks from the Seattle Mariners for first baseman Josh Naylor, sources tell ESPN. That's the full trade.
— Jeff Passan (@JeffPassan) July 25, 2025
And so begins deadline season. Buckle up.
Jerry DiPoto signaled that the Mariners intended to be buyers this summer, with a 1.5-game lead in the race for a Wild Card spot and one of the best and deepest rotations in baseball. The only thing that was missing was a little more offense — particularly at first and third base, where Donovan Solano and Ben Williamson weren't going to be enough.
Seattle was rumored for a reunion with Eugenio Suarez, but instead they opt for a different D-backs slugger in Naylor, who's slashing .292/.360/.447 on the year and will be a free agent this winter. What does this mean for the Mariners and their chances in the AL moving forward? And what about the return for Arizona, which seems to have finally come to terms with selling at the deadline? Let's break it all down.
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MLB trade grades: Mariners add much-needed pop with Josh Naylor addition
It's hard not to feel good about this from Seattle's perspective. Yes, Naylor is a rental, but he's also arguably the best non-Suarez bat available at the deadline, the rare first baseman who combines 25-homer power with excellent contact skills. He struggles against left-handed pitching, but the Mariners can still use Solano as the short side of a platoon, and he immediately lengthens this lineup in a meaningful way. If Julio Rodriguez can get on track and Randy Arozarena can stay hot, this is suddenly looking like a formidable heart of the order.
And they did it without having to give up all that much, all things considered. Garcia, Seattle's No. 13 overall prospect per MLB Pipeline, just made his MLB debut earlier this year after posting a 3.51 ERA in 33.1 innings across Double-A and Triple-A. He offers a wicked sinker/slider/cutter combination from the left side that can really eat up batters, but command (17 walks in the Minors this year) has been a serious issue at times, and that plus the lack of a real option again righties may well limit him to being a reliever moving forward. The same can be said for Izzi as well: A 2022 fourth-round pick currently in High-A, he's put up BB/9 over four in each of the past two seasons, and while his stuff might play up in relief, he might not have a deep enough repertoire to make it as a starter.
Even if they do wind up in the bullpen, Garcia and Izzi figure to be able to move pretty quickly and help Arizona's bullpen as early as next year. But the D-backs seemed to be holding much of the cards here, with maybe the two best bats available on the market. Giving up one without making their rotation appreciably better in 2026, with Corbin Burnes rehabbing from Tommy John and Zac Gallen and Merrill Kelly hitting free agency, feels like a missed opportunity.