Know Your Averages 2024, Changeup Edition

Fastball! Fastball! Inside-fastball!….changeup. It’s almost soothing, isn’t it? The hitter gets some relief from the loud, scary, onslaught of heat to a nice, easy, soft-dropping cambio. But don’t be fooled, that soft-cuddly change of pace can be absolutely devastating. It can send you right back to the dugout looking, and that’s if you’re lucky. If you’re unlucky, you just whiffed so hard a little snot came out of your nose, you made a loud grunting noise and possibly pulled a muscle in your lower back. Some pitchers utilize the changeup by only throwing it to opposite-handed hitters when they need it. Some throw it with regularity, lulling hitters to sleep. There’s no perfect way to use it, but a decent changeup in a pitcher’s arsenal can be a difference-maker. Let’s continue the “Know Your Averages” series with a pitch that’s thrown in the zone less often, rarely called for a strike, and chased like a rat terrier going after a….well…let’s just get to it.

Fastballs: Four-seamers | Sinkers | Cutters

Breaking and Offspeed Pitches: Sliders | Changeups | Curveballs | Splitters | Sweepers

The average Major League starter’s changeup usage peaked in 2020 and has been declining ever since. Reliever usage didn’t experience the outlier 2020 measurement that starter usage did, but it has also been in decline for the past few seasons:

You could probably write an entire book on the changeup’s usage patterns in the time period displayed above, or for any time period. But today, we’ll focus on 2024. My process relies on Alex Chamberlain’s Pitch Leaderboard which utilizes Statcast data that you can also find at Baseball Savant and our (New!) Pitch Type Splits on player pages. Here is a quick look at how the changeup stacks up against other non-fastball pitches in several measurements:

Let’s look at the pitchers below, at, and above average with their changeups in each measurement. A lot of what follows in the “Questions or comments?” section is less analysis and more points for further research or discussion.

NOTE: The chart and table above do not include a minimum pitch qualifier. The players in the analysis below will fall under a 100-pitch minimum qualifier with some arbitrary author finagling.

—Zone%—

• Miles Mikolas – 54.8%
• Kyle Harrison – 38.8%
• Jose Quintana – 20.0%

Questions or comments?: A changeup in the zone can be a good thing. In the case of Miles Mikolas in 2024, it wasn’t. His changeup was hit for a .394 batting average, a .479 wOBA, and missed bats (SwStr%) at a below-average 7.4% rate. Mikolas’ changeup, with no bat-missing stuff (84 Stuff+) and in the zone often, did not produce good results in 2024. It’s only fair to point out that when the ball was put in play, it fell in frequently, with a sky-high .386 BABIP. Similarly, Kyle Harrison’s changeup landing in the zone did not produce swing and miss. His 10.8% SwStr% was below average. Harrison desperately needs a pitch with which he can put away right-handed batters and his changeup produced better-than-average O-Swing rates against them in 2024. But, it wasn’t a “PutAway” pitch as it was the pitch to end the at-bat in a strikeout only 13.9% of the time. That’s good for one of the tenth-lowest marks among pitchers who threw it in at least 100 plate appearances. Lastly, Jose Quintana’s low Zone% worked for him in 2024 as he threw a pitch that shouldn’t have been in the strike zone anyway to produce above-average chase and above-average swinging strike rates.

—Swing%—

• Dakota Hudson – 31.8%
• Bryan Woo – 48.7%
• Tanner Gordon – 66.4%

Questions or comments?: Saaa-winggg battah! You’ll see below that Dakota Hudson got such low swing rates because he rarely located it in the zone. Bryan Woo reserved his changeup for opposite-handed hitters, throwing it 15.9% versus lefties and only 1.6% of the time against righties. He threw it for strikes and kept it low in the zone, an excellent recipe for the .243 wOBA pie he baked with his changeup in 2024. Tanner Gordon was changeup-heavy, but not outrageously so in 2024. He forced an above-average 14.7% SwStr% and generated a lot of that with an above-average chase rate, yet the pitch recorded a .469 wOBA. xwOBA thinks he was unlucky at .357, but he threw only two other pitches and played in Colorado.

—SwStr%—

• Dakota Hudson – 4.6%
• David Peterson – 12.7%
• Paul Skenes – 30.6%

Questions or comments?: Of the 151 changeups Dakota Hudson threw in 2024, only 7 were swung on and missed. No, he didn’t get more called strikes to balance things out. He mostly just missed the zone, resulting in 61.6% of his changeups being called for balls. Who else didn’t get swinging strikes on their changeup? Javier Assad (5.1%), Zach Eflin (5.4%), Aaron Nola (5.5%). But, Nola for example, limited wOBA on his changeup to .319 whereas Hudson’s got shredded for .469. What’s the difference? My guess is Aaron Nola has three other pitches graded above average by Stuff+ in his Knuckle Curve, Four-Seamer, and Sinker. Hudson does not. On the other end, Paul Skenes’ 2024 Changeup SwStr% was massive and it was chased out of the zone at a 45.7% clip, well above average. Who else returned major swing and miss on their changeup in 2024? Tarik Skubal (28.0%), Cole Ragans (27.8%), Jeffrey Springs (25.7%), and Blake Snell (25.7%).

—CallStr%—

• Paul Skenes – 1.8%
• Simeon Woods Richardson – 9.3%
• Tanner Bibee – 18.9%

Questions or comments?: Hitters should note that Skenes bullied them with changeups that were mostly out of the zone in 2024. My humble advice would be to stop swinging at it, but I know that’s about as easy to do as landing that bouncy ring on one of those Coke bottles at the county fair. The changeup is Simeon Woods Richardson’s best pitch by Stuff+. PitcherList’s loLoc% measures how often a pitcher locates their pitches “low of the batter”, and Woods Richardson didn’t do it often enough. If he can locate his changeup lower in the zone against lefties and improve his poor-performing four-seam fastball (77 Stuff+) he may be able to take a step forward in 2025. Lastly, James Paxton actually did worse than Skenes on the called strike front with only 0.9%, but I couldn’t pass over Skenes, who ruled the realm of swinging strikes. Unfortunately for the now-retired James Paxton, he couldn’t get anywhere near Skenes’ SwStr% and produced only an 11.6% mark.

—CSW%—

• Zach Eflin – 10.1%
• Luis Castillo – 22.0%
• Tarik Skubal – 39.6%

Questions or comments?: Zach Eflin got very few swinging strikes and even fewer called strikes on his changeup in 2024, and the result was a league-low CSW%. He located the pitch well enough, low in the zone, and only dealt with a .230 wOBA. It was mostly a pitch he used now and then to opposite-handed batters. Luis Castillo’s changeup got hit for a .364 wOBA in 2024, the pitch’s highest mark of its career. Tarik Skubal threw changeups all the way to the Cy Young award and its Stuff+ measure was near elite at 123.

—Chase%—

• Joe Musgrove – 17.1%
• Blake Snell – 28.2%
• Trevor Williams – 45.8%

Questions or comments?: Like many of the pitchers at the extreme ends of analysis, Joe Musgrove seldom threw his changeup. The pitch earned its second-lowest career chase rate and got tattooed for a .415 wOBA. Furthermore, it wasn’t chased often because it didn’t need to be. It was left in the zone an above-average 45.2% of the time. Blake Snell continued to toy with hitters utilizing his changeup in 2024 to produce a 24.1% SwStr%. He balanced that with in-zone and out-of-zone pitches. Lastly, Trevor Williams was able to generate chase with a pitch that was only in the zone 22.3% of the time compared to a 38.8% average. Since he rarely put it in the zone he rarely allowed hitters to square it up and the pitch generated only a .265 wOBA.

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There may not be any sweeping, clear-cut, or crystal-clear learnings from analyzing a bunch of different changeups. But one thing is clear, if you have a good one, you’ll be an entertainer on the mound. Next up, curveballs!