Andrés Muñoz’s changeup has gone from spring-training curiosity to one of the most difficult pitches in baseball to survive.
Back in 2025, the Seattle Mariners’ hard-throwing right-hander showed off a kick change-up in Peoria, Ariz., and it instantly got people talking. The pitch had as much as 10 inches of vertical drop, and Matt Brash didn’t exactly hold back on it, calling it the “best pitch I have ever seen.”
For all that buzz, though, the pitch barely mattered during the regular season a year ago. Muñoz used it only 22 times across 64 appearances, a tiny 2.1% usage rate.
That has changed in recent weeks. The 27-year-old closer has leaned on a more traditional changeup grip, and the results have been exactly what Seattle could have dreamed up and maybe even better.
The pitch has been untouchable.
Muñoz has a 100% whiff rate on his changeup this season. Every one of the 13 at-bats that have ended on the pitch has finished with a strikeout.
Tuesday night against the Red Sox was a clean example of how it plays. Facing left-handed hitter Wilyer Abreu in a save situation, Muñoz opened with a high fastball for a swinging strike, then buried two changeups that Abreu chased for a three-pitch strikeout. It marked the second straight night Muñoz had punched him out swinging on the pitch.
The changeup has also become a much bigger part of Muñoz’s plan against lefties, especially over the last month. He has thrown 48 changeups this season, and 47 of them have gone to left-handed hitters. Twenty-five have come in his last 12 outings since Aug. 1, after he had thrown 23 in his previous 41 appearances.
That usage has come with real payoff. Before Aug. 1, lefties were batting .241 with a .759 OPS against the Mariners’ two-time All-Star closer.
Since then, they’ve hit just .160 with a .462 OPS. Muñoz’s 15 strikeouts against left-handed batters since the start of August are also the second most among MLB relievers.
The numbers behind the pitch explain why it’s giving hitters so much trouble. Muñoz’s changeup averages 92.7 mph, which is 7 mph slower than his four-seam fastball. It also gets 5.6 inches more induced vertical break than comparable changeups, according to Baseball Savant.
FanGraphs gives the pitch a stuff+ grade of 121, with 100 as average. That ties it for the fifth-best mark among changeups thrown by MLB relievers. Paired with his slider, which is tied for the ninth-best grade among relievers at 130, Muñoz now has two of the nastiest weapons in the game.
Put them together, and hitters are managing only a .144 average, 17 for 118, with 62 strikeouts against his changeup and slider combined.
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