Miller's first full-effort bullpen cut short after oblique discomfort

March 11th, 2026

PEORIA, Ariz. -- ’s first full-effort bullpen session since suffering left side oblique inflammation was cut short before it got going on Wednesday afternoon, making an already tight window to break camp on the Opening Day roster even tighter.

Miller threw a handful of higher-intensity warmup pitches, then took what appeared to be a brief break before getting started with his actual full-effort pitches.

But those never came due to discomfort in the area, and once it was flagged, Miller and the Mariners cut the session short.

“This is rehab,” Mariners general manager Justin Hollander said. “This is part of it.”

Miller will not be shut down from throwing altogether and is expected to still have the green light to play catch in the coming days.

If that goes well, he could throw a touch-and-feel ‘pen over the weekend or early next week, like the one he threw on Sunday at what he estimated was around 80-90% effort. From there, the Mariners would try again at a full-effort bullpen three or four days later, or essentially about one week from now.

“This is just part of that process. ... Some days, you feel a little tightness, and we back it down,” Hollander said. “Sometimes, you feel great, and you feel like you're ready to take the next step. He wasn't ready to take the next step today and smartly said, ‘I'm not ready to take the next step today,’ so we'll try again in a couple days.”

Hollander didn’t want to rule out Miller’s status for Seattle’s Opening Day roster, but the calendar’s mathematics suggest that -- even in a best-case scenario -- he won’t be built back up by then.

Even if they were to roll him out as their No. 5, that spot would come on March 30 against the Yankees, 19 days from now, and they’d need an arm capable of five to six innings and/or 80 to 90 pitches by then.

“He's behind schedule, and I think that's obvious,” Hollander said. “But beyond that, it'd be silly for us not to have contingency plans every year for starting pitchers and make sure that we have enough guys to open up with five to start the season.”

With the setback, that workload capacity for Miller would still be weeks away -- not to mention that this is March and not October, meaning that extra caution will be exercised with the intent to preserve both the season’s longevity and Miller’s health.

And again, while oblique injuries are notorious for lingering, a silver lining in Miller’s situation is that it’s not arm-related, especially after two stints on the injured list last season related to bone spurs in his pitching elbow.

“We're not going to push through this and risk having to actually take a step backwards, so he doesn't need to be shut down from throwing,” Hollander said.

That said, the Mariners do have more immediate decisions looming on what to do with their fifth rotation spot.

The most obvious candidates are right-handers Emerson Hancock (their de facto No. 6 for the past two seasons, who’s been their primary injury fill-in) and Cooper Criswell (who, independent of Miller’s situation, was expected to break camp as a long reliever).

Left-hander Kade Anderson, Seattle’s No. 2 prospect and MLB Pipeline’s No. 21 overall, is not expected to be considered for the rotation this early, as he still hasn’t pitched in any pro capacity outside of his two Cactus League starts this spring.

“I don't really want to get into where we're at roster-wise now,” Hollander said. “[Miller] is definitely behind where you would want to be to make the roster by Opening Day. But we'll make decisions when we need to make decisions on that.”

Hancock probably has the upper hand given his incumbency, and he’s been stretched out as a starter in Spring Training for this very reason, after transitioning to a relief role last August based on a specific roster need at the time.

Criswell is also being stretched out, having worked 3 1/3 innings and 57 pitches over his most recent start on Tuesday. And he does have starter experience, with 21 such outings in his career, including 18 of them coming in 2024 for the Red Sox. But he will most likely wind up in the bullpen, and the fact that he’s out of Minor League options makes him more of a priority for the Opening Day roster.