Andrés Muñoz’s season has had its rough stretches, and Sunday’s blown save against the Athletics was another one. But tucked inside the volatility is a development that could change the way the Mariners closer is deployed down the stretch: his changeup has turned into a nightmare for hitters.
The numbers are absurd. In 19 at-bats that have ended on Muñoz’s changeup this season, opponents are 0-for-19 with 17 strikeouts.
On 29 swings, hitters have whiffed 24 times, an 82.8% miss rate that borders on cartoonish. The pitch also carries a .012 expected batting average and a .013 expected slugging percentage, which only reinforces how little damage anyone has managed against it.
“I think it’s a pitch that can be unhittable,” Mariners manager Dan Wilson said.
That’s not just talk anymore. Muñoz barely leaned on the changeup for much of 2026, instead relying mostly on his slider, sinker and four-seam fastball.
Through the end of July, he threw the pitch only 3.5% of the time. Since the start of August, that usage has jumped to 14.8%, a clear sign that it has moved from curiosity to real weapon.
The boost has come with help from Cal Raleigh and the Mariners’ other catchers, who have seen the pitch’s potential and started calling it more often.
“I feel a lot more comfortable with that pitch right now,” Muñoz told MLB.com. “I trust a lot in the catchers.
They can tell me when it’s a good pitch. Even if I am missing some of the spots that I want to hit, they know when that pitch has good movement, and that’s the reason why they started calling them more.”
The pitch has also gotten harder to square up because of the way Muñoz has built it up over the year. He has added nearly 3 mph to the changeup since the start of the season, and over the last two months it has averaged 93.5 mph. That makes it look even more like his 99.7 mph four-seam fastball before it disappears below the zone, with 4.2 inches more vertical drop on average than comparable changeups.
“The best thing for a pitcher is to throw different pitches that look the same,” Muñoz said. “As soon as that thing looks like a fastball and then drops, I think it’s a great pitch.”
Because of that speed and movement, Muñoz doesn’t need to live in the strike zone with it. Just four of his 62 changeups this season have been in the zone, and two more only clipped the outside edge.
“As long as you can start it in the zone and let it run out, it’s a really tough pitch to lay off of,” Wilson said.
One of the few times Muñoz has used it on a right-handed hitter came May 11 in Houston, when he surprised Astros star Jose Altuve with an 0-1 changeup down the middle. Otherwise, the pitch has been used almost entirely against lefties, though Muñoz said he’s open to expanding that.
“I’d have to look at that,” Muñoz said. “But I am up to throwing it to righties. That would depend more on the catcher, what he thinks about this hitter, or things like that.”
It’s a long way from where the pitch started during 2025 Spring Training, when Muñoz debuted it as a “kick-change,” with his middle finger lifted off the ball to create horizontal spin. That version didn’t stick, and Muñoz said he couldn’t control it well enough.
This year, the grip and delivery have stayed the same, but the intent has changed. Muñoz has thrown it harder, trusted it more and watched it turn into something far more dangerous.
“When you start throwing something new, you are a little bit more concerned about, ‘Is this the right pitch to throw?’” he said. “With time, you start to throw it more and get more comfortable with it.”
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