Josh Naylor's walk-off grand slam should deepen Mariners' trade desperation

Watching the Seattle Mariners try to score runs this June has been an exercise in frustration — and futility. With just two wins in their 10 games played this month, the offensive ineptitude has boiled over. Nothing quite captured the current state of despair like the gut punches delivered by the Arizona Diamondbacks in their most recent series.

First came Josh Naylor’s walk-off grand slam to open the set on Monday. Then, in the finale, former Mariner Eugenio Suárez twisted the knife with a go-ahead grand slam off Bryan Woo.

For Mariners fans, it wasn’t just the loss — it was the symbolism. Suárez reminded the club what they gave up. Naylor reminded them what they never had the guts to go out and get.

Josh Naylor proved he’s the missing piece in Seattle’s lineup

The Mariners have been linked to Josh Naylor dating back to this past offseason. In December, Adam Jude of the Seattle Times reported that Seattle had discussions with the Guardians about acquiring the slugging first baseman. However, the Diamondbacks swooped in and landed Naylor in a deal that cost them right-hander Slade Cecconi and a competitive balance Round B pick — a package well within reach for a pitching-rich Mariners farm system.

That failure jumps off the page even more after their latest three-game set. Naylor has been everything the Mariners need and don’t have.

Seattle first basemen have produced an abysmal .626 OPS and a combined -0.6 WAR in 2025. Naylor, meanwhile, owns a .818 OPS, eight home runs, and 45 RBIs — good for a 1.1 WAR. He’s bringing pop from the left side of the plate, strong plate discipline, and clutch performances to a Diamondbacks lineup that still sits fourth in the NL West, 6.5 games out of the division lead. It’s a team teetering between contention and sell mode, and Naylor — on an expiring deal — is one of their most obvious trade chips.

Make no mistake—the Mariners are desperate, and rightfully so. Their grip on the AL West has slipped, and their once-dominant pitching staff is now in disarray due to injuries. What remains is being completely wasted by a lineup that can’t support it. The corner infield spots, in particular, have become offensive black holes.

Jim Bowden of The Athletic recently highlighted Naylor as the ideal trade target for Seattle, citing his left-handed power and short-term cost, writing, “His left-handed power would be a difference-maker in the middle of the Mariners’ lineup.”

He’s right. And the Mariners are running out of time to fix what they’ve failed to address for months.

There’s also a comfort level here. The Mariners and Diamondbacks have made deals before, even if some of them loom as a sore spot. But it shows there’s a line of communication. And while the D-backs may have just taken the series, they still face long odds in a brutal division. If they do decide to sell, Seattle should be at the front of the line, armed with arms and ready to make amends.

Josh Naylor just showed the Mariners what he’s capable of — one violent swing at a time. If Jerry Dipoto is serious about making this season matter, he can’t miss again. The Mariners need a bat. They need Josh Naylor.