Know Your Averages, Curveball Edition

Are you a hitter who can’t time up the fastball? Feeling over-powered? Not having your best day? Just wait it out, the hook will come eventually. Keep that weight back and search for that little bump, that little loop, as the pitch comes towards the plate. Wait on it, wait on it, wait on it….strike! It’s not as easy as it sounds. Of the 115 starting pitchers who threw at least 100 innings in 2024, 76 threw a curveball. Some of them got blasted; Miles Mikolas, Pablo López, Jameson Taillon. Some of them did the blasting; Framber Valdez, Seth Lugo, Max Fried. Take a look at some finer details below and see if you can find a few pitchers with positive curveball metrics for the back end of your fantasy rotation.

Fastballs: Four-seamers | Sinkers | Cutters

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

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 curveball stacks up against other non-fastball pitches in several measurements:

Let’s look at the pitchers below, at, and above average with their curveballs 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%—

• Yoshinobu Yamamoto – 59.4%
• DL Hall – 43.9%
• Bryce Miller – 21.3%

Questions or comments?: Yamamoto’s curveball landed in the zone (58.2%) more often than his sinker (57.1%) did! How common is that? My guess is not very. Sinkers are the most “in the zone” fastball and Yamamoto has a unique combination of throwing his curveball in the zone often while keeping his sinker working on the inside against right-handed batters. DL Hall’s curveball usage increased to 22.9% against righties (opposite-handed ) while Bryce Miller’s stayed at a low 6.3% against opposite-handed hitters. A curveball in the zone can be a great thing if it can fool hitters into taking a strike while also producing swing-and-miss when the hitter attacks. A sweet combination of above-average Zone% and CSW% can turn a secondary into a weapon.

—Swing%—

• Grant Holmes – 46.9%
• Max Fried – 40.5%
• Michael Wacha – 22.1%

Questions or comments?: Grant Holmes’ curveball was his best pitch by Stuff+ and nearly by SwStr%. Only his slider earned more swings and misses. Watch out! Holmes is a righty with two breaking balls with above-average SwStr%. Sadly, neither of his fastballs are all that good. Neither the cutter nor the four-seam grade out to average by Stuff+ and neither pitch returned better than average SwStr rates. Wa-cha, wa-cha, ah-wa-cha want?!? More swings on Wacha’s curveball. His 2024 version was beat up for a .422 wOBA. Lucky for him he threw it less than 10% of the time to all hitters.

—SwStr%—

• Blake Snell – 23.7%
• Ryan Feltner – 11.7%
• Nick Martinez – 3.5%

Questions or comments?: Snellzilla did it in 2024 with his curveball. It was his best pitch by wOBA (.174), by O-Swing%, and by K%. In 2024, he had one of the best SwStr rates with his curveball, but it wasn’t even his best pitch by that measurement. Take a look at the past few seasons and Snell’s best pitch by SwStr%:

2021: Slider (23.2%) -> 2022: Slider (23.9%) -> 2023: Changeup (24.3%) -> 2024: Changeup (24.1%)

When a pitcher has that many good secondaries, he’s worth rostering on a fantasy team, and often. Ryan Feltner snuck in 162.1 innings last season with the Rockies and kept his ERA below 4.50. Now, that’s something. His curveball had solid Stuff+ grades and did well with only a .202 wOBA. He’s also a guy with two fastballs and solid secondaries. Nick Martinez’s curveball did not fair so well with a .399 wOBA. Throwing it only 12% of the time allowed him to finish the year with a 3.10 ERA. A lot of good things happened for Martinez in the last few months of the season to even out his final stat lines, including a .214 BABIP.

—CallStr%—

• Reid Detmers – 30.3%
• Seth Lugo – 18.8%
• Andre Pallante – 6.6%

Questions or comments?: Reid Detmers may have been able to get a healthy dose of called strikes with his curveball, but he got an unhealthy dose of wOBA, .504. The pitch gave up five home runs in 2024 and seemingly didn’t fool hitters the second time. High called strike rates can be misleading especially if they are not paired with swing and miss. Detmers’ curveball only produced a 7.0% SwStr%. Seth Lugo’s curveball was his dominant pitch, which he utilized 26% of the time and graded as above average by Stuff+. Never in its career has the pitch gone above a .290 wOBA and in 2024, Lugo earned his highest SwStr% with the pitch at 15.2%. For those of us who still like pVals, Lugo’s curve returned an 11.7! Palante couldn’t get many called strikes but did well with swinging strikes at an above-average 14.8%. He accomplished many of those with a high chase rate.

—CSW%—

• Yoshinobu Yamamoto – 43.4%
• Nick Pivetta – 30.4%
• Carlos Carrasco – 17.9%

Questions or comments?: Yamamoto’s 2024 curveball was a line in a song. Singing a sad song was Carlos Carrasco’s curveball CSW%, but that’s only because his called strike rate was so low. He didn’t place his curveball in the zone often, and that produced higher chase rates. It all balances out.

—Chase%—

• Bryce Miller – 36.1%
• Randy Vásquez – 24.0%
• Yoshinobu Yamamoto – 14.5%

Questions or comments?: Do you see the Yamamoto pattern? His curveball achieved a high zone rate, a high called strike plus whiff rate, but a low chase rate. The way he attacked hitters left those who would take with a strike and those who would swing with one as well. Both his SwStr% (13.2%) and his CallStr% (29.2%) were above average. You simply couldn’t win against the pitch as a hitter in 2024. Bryce Miller experimented with 18 curveballs in 2023 and delivered 122 knuckle-curveballs in 2024. They returned a .232 wOBA and a 13.9% SwStr%. Miller has two above-average fastballs in the sinker and the four-seamer, both of which are above-average by Stuff+, and he has a great secondary, as proven by SwStr%.

—

For starting pitchers who want to throw a curveball, the path to success seems clear. Make it difficult to hit when it’s in the zone and you’ll get both called strikes and whiffs. Pair it with a good fastball, ney, pair it with two good fastballs and you’ll really be onto something. Add in a second secondary that also gets swing and miss, maybe even a little chase, and you’ll be the team’s ace. That all sounds pretty challenging, though. What are you doing reading this stuff? Get to work.