Muñoz searching for form as Mariners remain confident in closer

SAN DIEGO -- One day after what he called the worst outing of his career, Andrés Muñoz remained hard on himself when reporting to Petco Park on Thursday.

“I need to find myself again,” Muñoz said.

Less than 24 hours prior, the Mariners' closer was charged with a career-high five earned runs during the bottom of the ninth inning of a walk-off, 7-6 loss. That was the brutal bookend to a night in which the Mariners played some of their best baseball of the season’s first three weeks.

Any player would be hard on himself if he were the culprit of such a glaring moment. But Muñoz also has most of his extended family here visiting from Mexico, was playing against the organization he grew up in and isn’t accustomed to such pronounced struggles.

Yet, Mariners manager Dan Wilson will have zero hesitation to install the two-time All-Star at a moment’s notice if the pocket is right -- unless Muñoz needs rest.

“Outside of that, I think we feel pretty good about where he is,” Wilson said.

Physically, Muñoz is fine. Mentally, outside of Thursday, he is, too. Mechanically, same.

In fact, Muñoz can pinpoint the exact cause of his issues. But now comes the challenge of correcting them on the tightrope of a closer’s role, where there are no in-between sessions to work on things like a starter.

Specifically, Muñoz is looking to reharness the grip of his elite slider, which lacked deception throughout Thursday and has eluded him at times throughout this young season. That pitch accounted for each of the four balls to his leadoff batter, Manny Machado, and the two-out double to Luis Campusano that ended his night.

Muñoz did strike out Nick Castellanos with the pitch, albeit one that the slugger chased way out of the zone. And, perhaps ironically, his best-executed slider was turned around for a 55.5 mph double by Gavin Sheets, a tough break that became more exacerbated because nothing else was going right.

“It's a grip thing,” Muñoz said. “Normally, I just have the grip, throw it as hard as I can, and now I have to find that grip. It's feeling weird, and it's been like that since last year, too. And we talk about this a lot; it's my best pitch. And if I don't have my best pitch, it's tough to go out there. Even if my other pitches are good, you feel like you don't go out there with your best weapon.”

Indeed, Muñoz held hitters to a .109 batting average and .133 slugging percentage against his slider in 2025 -- MLB’s second-best marks among 162 pitchers who threw one at least 250 times, behind only Mason Miller on each. This year, hitters are 3-for-19 (.158) against it with eight of his 10 strikeouts.

That pitch has soared past both his fastballs, and has allowed him to thrive despite seeing a velocity dip on his heaters, from a 100.2 mph average in 2022 to 98.2 mph in ‘25, when he racked up a career-high 38 saves.

“After I release it, it just doesn't feel good,” Muñoz said. “It doesn't feel like I have the same whip like I have with the fastball. And probably, that is causing them to [be able] to see it, or they can know before. As soon as they see the ball, the way that [it spins], or the way that it starts, they can see if it's going to be a slider or a fastball.”

That said, Mariners director of pitching strategy Trent Blank isn’t nearly as concerned. Blank typically assesses relievers by chunks of 6-8 outings rather than a handful; Muñoz has made seven. That, and Seattle’s proprietary projections actually show upside on the pitch.

“Truthfully, I don't see maybe the same things he's seeing,” Blank said.

There’s been variance on the slider, Blank said, but not out of the norm. It’s generated a 48.9% whiff rate with a spin rate average of 2,304 RPM -- both in line with last year’s numbers.

“He does have some big misses here and there, but yeah, sometimes I think these results create a different image in your head versus what's actually happening,” Blank said. “And we're going to help him separate through that noise.”

To be sure, the pitch didn’t look right on Thursday, and the Padres ambushed him for it. But at least for now, this doesn’t seem to be as massive a concern for the Mariners as the disastrous outcome suggested.