Mariners fans are already stressing about shaky rotation's playoff outlook

The Seattle Mariners have had a solid season when you zoom out and look at the bigger picture. Solid. But frustrating. In a year where the offense has finally shown signs of life, there’s still an undeniable cloud of disappointment hanging over the team. Why? Because when a Mariners offense ranks seventh in all of Major League Baseball, you should be bulldozing your way to a division title.

Instead, the Mariners are barely clinging to the hope of an AL West crown, and the culprit isn’t hard to find — it’s the starting rotation.

For years, fans and analysts alike begged this front office to just get some bats. The pitching had been elite. The bullpen strong and the defense clean. All Seattle needed was some thunder in the lineup. And this year, they got it, or at least enough of it to matter.

But now the pitching has fallen off a cliff.

Mariners fans are bracing for a playoff run without their usual pitching backbone

Seattle’s staff, which ranked in the top five in ERA and WAR the last two seasons, has slipped to 17th in ERA and 19th in WAR here in 2025. And the timing couldn’t be worse with October looming and no clear answers forming around the struggles in the rotation.

So what’s left? Hope, basically. Hope that somehow this group channels the 2023/2024 version of itself in the final weeks. Hope that they step up and reestablish dominance on the mound. Because without that, it’s tough to see how this team gets out of the first round.

Recently, Eno Sarris of The Athletic attempted to answer this question by ranking the most feared three-man playoff rotations if the postseason began today. Among all 12 playoff-bound teams, Sarris slotted the Mariners fifth. Respectable. The trio he listed?

• Luis Castillo (9-8, 3.85 ERA)
• Logan Gilbert (4-6, 3.61 ERA)
• George Kirby (8-7, 4.47 ERA)

Sarris went on to note: “If you get to the longer series, then their No. 4 starter Bryan Woo and No. 5 starter Bryce Miller are likely better than just about anyone else’s fourth and fifth options. That’s for sure.”

On paper, that looks like a decent group...If we were talking about last year.

And respectfully, national rankings can miss a few things, that’s just how it goes. But if you’ve been watching the Mariners this year, and we mean really watching, there’s one omission that’s hard to ignore.

Bryan Woo.

Let’s be real: if the Mariners rolled into October with Castillo in the Game 1 slot, fans wouldn’t just question the rotation, they’d question the front office’s actual desire to win. It sounds harsh, but Castillo hasn’t looked like an ace this year. He’s been inconsistent, hittable, and downright shaky in key spots.

Meanwhile, Woo has been far and away the most reliable starter on the team. At times, he’s felt like the glue holding the entire rotation together. And he’s legitimately the only Cy Young candidate (albeit a long shot) in the Mariners’ rotation.

This team doesn’t operate on nostalgia or reputation. Just ask Dan Wilson or anyone else around the organization this season. They’ve lived and died by the ‘What have you done for me lately?’ mantra. And lately, Woo has looked like the guy you’d hand the ball to with your season on the line.

A more accurate playoff rotation, based purely on 2025 production might look like:

• Bryan Woo (13-7, 3.02 ERA)
• Logan Gilbert (4-6, 3.61 ERA)
• George Kirby (8-7, 4.47 ERA, though it’s worth noting that the ERA is inflated due to injury.)

Notice the absence of Castillo? It’s not personal. It’s just the reality.

But even with Woo’s rise, the broader issue remains: this isn’t the dominant Mariners rotation fans are used to. Seattle starters have a 4.10 ERA overall, and a 4.35 mark in the second half. That’s not going to cut it in a short playoff series, especially not without home-field advantage. The team has struggled on the road (34-41), and without a bullpen capable of shortening games like it once did, the pressure on the starters becomes enormous.

Seattle needs quality starts. Period. Because the safety nets aren’t as reliable this year.

There’s still time to figure it out. But as it stands right now? Mariners fans aren’t crazy for being nervous. They’re just paying attention.