Starting Pitcher Arsenal Changes - Pitch Mix Analysis for Fantasy Baseball (Week 10)

May 29, 2025

Corbin Young examines several fantasy baseball pitcher risers and sleepers displaying changes in their pitch mix, movement, and velocity heading into Week 10 (2025).

Welcome back, RotoBallers, to my weekly "Starting Pitcher Arsenal Changes" article series for Week 10 of the 2025 fantasy baseball season. We researched 27 starting pitchers so far, with three more in this column, all of whom flashed were top prospects. Today's article will discuss a few starting pitchers who made actionable adjustments, like a release point change or a new pitch, location changes, and whether they matter moving forward.

For those new to this column, we cover a few starting pitchers and their arsenal changes via pitch mix, velocity, and movement each week. Since it's early, we're looking for new pitches, velocity, and movement changes. When we find significant release point shifts, it can potentially impact their movement profiles in 2025.

Pitchers can make notable changes in smaller samples, so let's see if we can find something with these starting pitchers. Statcast provides so much data to digest and compare quickly to past seasons. Let's look through my process of examining starting pitchers and their arsenals. Reach out to me on X if you have a pitcher and have questions about it. Thank you for reading!

Jack Leiter Changed His Righty Approach

Leiter adjusted his approach against right-handed hitters by throwing more sliders (40.3 percent) and lowering the four-seam usage (34.2 percent). That's a 10-13 percentage point change for the slider and four-seam versus righties. Leiter mixed in a sinker more often in 2025 (16.4 percent).

His pitch results improved for his primary offerings versus righties, including the slider (.215 wOBA, .295 xwOBA) and four-seam (.284 wOBA, .329 xwOBA). Meanwhile, Leiter's sinker allows a .258 wOBA, though the expected wOBA (.424) suggests regression. The data suggests Leiter's new approach against right-handed hitters has been positive, but be cautious, unless the pitch movements and locations change.

Leiter's Lower Arm Angle

Though Leiter's arm angle dropped four degrees, he maintained his near-elite levels of extension from his high arm slot. Why did Leiter's arm angle change? It's mainly because Leiter's horizontal release point moved farther away from his midline by nearly three inches (2.6) in 2025. That coincided with Leiter maintaining his vertical release point.

Leiter's four-seam lost a half-inch of induced vertical break (IVB) with the slight arm angle change. His four-seam still possesses above-average IVB, which theoretically should bode well with the high extension. However, Leiter's four-seam locations have been the issue. Location aside, Leiter's four-seam lost three percentage points of swinging strike rate (10.8 percent) in 2025 compared to 2024 (13.8 percent).

Furthermore, Leiter has been throwing the four-seamer in the zone less often by nearly seven percentage points to 50.8 percent in 2025. Leiter threw his four-seam in the upper third (an ideal spot), 29.1 percent of the time in 2024. However, his four-seamers were thrown in the upper third only 14 percent of the time in 2025.

Maybe it's the lower four-seam usage or the location changes have been a concerted effort. Like Leiter lowering the four-seam usage against righties, he dropped it to 34.2 percent in 2025, coinciding with better outcomes (.284 wOBA, .329 xwOBA).

Given the induced movement profiles and locations between the four-seam and sinker, there's a possibility that he can toggle between both fastballs. That's especially notable since his sinker usage increased with a dip in four-seamers, though there might be a pitch classification issue.

Leiter's New Changeup

Kennedi Landry, Rangers beat writer for MLB, discussed Leiter's new sinker and changeup in the offseason. Sometimes those notes can be noisy, but there's evidence with Leiter's new changeup in 2025. Leiter is using a new changeup grip, where his middle finger is bent with somewhat of a "kick change" grip.

That led to Leiter's changeup adding five inches of vertical movement while losing three inches of arm-side fade. Besides Leiter's changeup adding downward movement, the spin rate fell over 300 RPM (1,526 RPM), almost turning into a splitter, where the movement can vary. For context, Kevin Gausman's typically nasty splitter has a spin rate of around 1,700 to 1,800 RPM.

Unfortunately, Leiter's changeup hasn't elicited more whiffs, with a 10.1 percent swinging strike rate in 2025, down over two points from 2024 (12.8 percent). If Leiter's changeup doesn't induce more whiffs, does it generate weak contact? That hasn't been true against left-handed hitters, with the changeup allowing a .296 wOBA (.357 xwOBA) in 2025. We would speculate that Leiter's changeup location is the challenge.

One assumes that a changeup drops more, so the locations should be in the lower third of the zone. That hasn't been the case with Leiter's changeup. Leiter's changeup zone rate jumped by 10 percentage points to 46.4 percent (2025) from 35.9 percent (2024). Hitters crushed the changeup when it was thrown in the zone in 2025, evidenced by a .434 wOBA (.353 xwOBA) versus a .000 wOBA (.222 xwOBA) in 2024.

Given the spin rate and grip changes, there's a chance Leiter struggles to command and locate the changeup in 2025. That would align with how splitters typically operate, where it can be challenging to command.

Summary

Though Leiter showed some interesting pitch arsenal metrics, his skills haven't taken a step forward. Leiter's xERA (4.96) is slightly worse than his actual ERA, but his skills have taken a step back. That's evident in Leiter's below-average swinging strike rate (10.2 percent) and strikeout minus walk rate (5 percent). Leiter made several actionable changes in the offseason, translating to the regular season, so expect more whiffs and better skills coming soon.

Tarik Skubal's Sinker Changes

Skubal has been throwing his sinker harder in 2025 (97.7 mph), 1 mph faster than in 2024 (96.9 mph), and around 2 mph faster than in 2023 (95.8 mph). With the sinker's velocity increase, it lost over two inches of downward movement and 1-1.5 inches of arm-side fade. Before examining the locations, let's review the sinker results versus left-handed hitters.

Skubal's sinker has been a consistent part of his arsenal against left-handed hitters. However, he lowered the usage to 40.7 percent in 2025, over 15 percentage points below 2024 (55.8 percent). Skubal's sinker usage dipped in 2025, but the outcomes improved. That's evident in Skubal's sinker, allowing a .159 wOBA (.175 xwOBA) in 2025 versus a .259 wOBA (.261 xwOBA) against left-handed hitters.

Since Skubal's sinker lost downward movement, it unsurprisingly generated fewer groundballs at 48.9 percent. That's notable because Skubal's sinker resulted in a 55.7 percent ground-ball rate in 2024, following a similarly high rate in 2023 at 75.9 percent. Besides the sinker's missing downward movement, the locations have been slightly more toward the inner half of the plate for left-handed hitters.

There's also a chance Skubal's sinker pairs well with the four-seamer, making it challenging for hitters to predict.

Skubal's Changeup Velocity Increased

Skubal's changeup added 2 mph of velocity in 2025. That led to the changeup losing over two inches of vertical movement. Meanwhile, Skubal's changeup added around an inch of arm-side fade. A pitch that loses downward movement typically doesn't maintain swinging strikes. However, Skubal's changeup swinging strike rate (29.4 percent) in 2025 is similar to his recent seasons, around 26-27 percent.

Skubal's changeup has been deadly against right-handed hitters, allowing a .192 wOBA (.201 xwOBA). Meanwhile, Skubal's changeup has a .000 wOBA (.116 xwOBA) versus left-handed hitters.

The locations have been slightly more concentrated for Skubal's changeup, throwing it down and away from right-handed hitters 33.5 percent of the time in 2025 versus 24.8 percent in 2024. Regardless, Skubal's changeup has remained effective to induce weak contact and whiffs over the past few seasons.

Summary

Skubal has been the elite starting pitcher fantasy managers drafted, with a 2.52 xERA, 32 percent strikeout minus walk rate (career-best), and a 19.1 percent swinging strike rate (career high). He has been continuously evolving as a pitcher by adjusting his pitch mix against both sides of the plate, adding velocity and showing better command.

The only minor question mark is Skubal's approach against right-handed hitters in 2025, with the four-seam (.303 wOBA, .347 xwOBA), sinker (.302 wOBA, .352 xwOBA), and slider (.420 wOBA, .367 xwOBA) besides the changeup. Will Skubal's pitches improve and regress closer toward 2024?

Edward Cabrera's Arm Angle Dropped

There's no denying Cabrera's stuff throughout his career, but it's been a matter of consistency and command for him. Cabrera's arm angle dropped to a career low of 36 degrees in 2025. His vertical release point dropped by 1.5 inches, with the horizontal release shifting nearly four inches away from his midline (3.8).

It's worth noting that Cabrera's horizontal release points regressed closer to what it was earlier in his career, around 1.7 feet. However, Cabrera maintained farther horizontal release points with a higher vertical release in previous seasons, 1.8-2 inches higher than in 2025.

Theoretically, Cabrera's lower arm angle should bode well for his pitch-level horizontal movement profiles, with some potential changes in the vertical movement. Cabrera's changeup and sinker added 1.5 inches of arm-side fade in 2025, leading to above-average horizontal movement profiles.

Cabrera's Remade Curveball Movement

Cabrera's curveball added two inches of sweep toward his glove side. Besides the additional glove-side movement, Cabrera's curveball added 4-7 inches of downward movement compared to the previous seasons.

Cabrera remade his curveball in 2025, aligning with the arm angle and release point adjustments. In 2023 and 2024, Cabrera's curveball was effective against right-handed hitters, and the expected numbers may regress in 2025 (.474 wOBA, .246 xwOBA).

Meanwhile, Cabrera's curveball remained effective versus left-handed hitters, given the .253 wOBA allowed (.204 xwOBA) in 2025. The curveball locations haven't changed much from previous seasons, though the results have remained positive, especially when he locates it low and below the zone.

Cabrera continues to rely heavily on the slider, curveball, and changeup. However, he has been throwing more sinkers in 2025.

Cabrera is Throwing More Sinkers

Cabrera used to throw his sinker 12-14 percent of the time from 2022 to 2024 against right-handed hitters. However, Cabrera increased the sinker usage to 28.7 percent versus righties, leading his arsenal. Unfortunately, Cabrera's sinker results have been horrible, allowing a .436 wOBA (.429 xwOBA) versus right-handed hitters.

Cabrera's sinker added 1.5 inches of arm-side movement, making it a pitch he theoretically should pound inside toward right-handed hitters. That should lead to weak contact, but Cabrera has been throwing his sinker in the heart of the zone, where hitters can crush it.

Even when Cabrera throws the sinker toward the inside corner to right-handed hitters, it continues to be destroyed. The sinker isn't nasty enough to be thrown in the zone as often as he throws it. He has been throwing the sinker in the zone 65.2 percent of the time in 2025, though it hovered more around 40-41 percent in recent seasons.

This goes back to Cabrera's skills and profile being a stuff-over-command type pitcher. Give Cabrera some time, since we might have to be patient with him.

Summary

Cabrera's xERA (3.84) is nearly one run better than his actual ERA (4.72). Control remains an issue, with a 38.1 percent ball rate in 2025 and a career 39.4 percent ball rate. His overall swinging strike rate dipped to 10.7 percent (2025) from 12.2 percent (2024). One aspect we didn't touch on with Cabrera involves his changeup losing whiffs from a 16.5 percent swinging strike rate in his career to 10.6 percent in 2025.

We could speculate that Cabrera's lower arm angle negatively impacts the changeup in the early 2025 sample. Though his changeup dropped three inches more in 2025 than in recent seasons, the usage dipped to 17.8 percent (2025) from 31.2 percent (2024), with fewer whiffs and worse results. Cabrera's right-on-right changeups haven't been as effective, and it's something to monitor for a future examination.

Download Our Free News & Alerts Mobile App

Like what you see? Download our updated fantasy baseball app for iPhone and Android with 24x7 player news, injury alerts, sleepers, prospects & more. All free!

More Fantasy Baseball Analysis