Statcast Pitcher Studs and Duds - Advanced Metrics Leaders for CSW% (Week 14)

June 27, 2023

Connelly Doan examines fantasy baseball pitcher risers and fallers, and whose CSW% could make them adds, drops, or trade targets for Week 14.

Welcome back to another edition of RotoBaller’s Statcast Pitcher Studs and Duds article series! Each week, I will select one advanced metric, choose two pitchers with strong values and two with poor values, and analyze what those values may mean for future performance.

I have written about several strikeout and strike-generating metrics this season. Strikeouts obviously play an important part in both roto and points fantasy leagues, so I have taken a look at them from various angles. One broader and newer metric I have yet to look at is called + swinging strike rate (CSW%). CSW% is as it sounds; it is the percentage of pitches that are called strikes and swinging strikes.

Fantasy managers will need to take stock of their rotations as the first half of the fantasy season wraps up. Identifying pitchers who have generated strikes and how can be a helpful exercise in determining how solid their rotations may be. Without further ado, let's analyze some CSW% Studs and Duds!

CSW% Studs for Fantasy Baseball

All stats are current as of Sunday morning, June 25, 2023.

Charlie Morton, Atlanta Braves

6-6, 3.71 ERA, 1.45 WHIP, 31.4% CSW%

Charlie Morton has been a strikeout asset in fantasy for some time now and this season has been no different. The 39-year-old has provided much of the same this season, going 6-6 with a 3.71 ERA, 1.45 WHIP, and 26.2% strikeout rate. Impressively, his 31.4% CSW% is third among qualified starters. Morton has had an up-and-down season overall, so what can fantasy managers expect in the second half?

Morton's pitch mix approach has mirrored what it has the past several seasons, relying heavily on a devastating curveball and an above-average fastball. He has pounded the strike zone with his fastball at a 57.9% rate and has gotten a lot of swinging strikes with his curveball at 18.7%. Interestingly, his current CSW% is actually a bit higher than it has been the past couple of seasons but his strikeout rate is a few percentage points lower.

Charlie Morton, Nasty 83mph Curveball...with 3175 RPMs 😨 pic.twitter.com/ld2TTzWmJl

— Rob Friedman (@PitchingNinja) June 25, 2023

Morton's strikeout skills have been strong, but there are other aspects of his game that could be better. His inflated WHIP has been due to both an increased walk rate of 10.1% and a .335 BABIP. Morton has thrown his pitches in the zone frequently but has only gotten a strong batting average against with his curveball.

Morton has presented a mixed bag of stats so far this season. His strikeout metrics have been strong and seem well-supported.  However, he has also thrown more pitches out of the zone and has allowed damaging contact in the zone. Overall, I think fantasy managers' best bet is holding onto Morton knowing that he will deliver the occasional dud start.

Clayton Kershaw, Los Angeles Dodgers

9-4, 2.72 ERA, 1.10 WHIP, 30.6% CSW%

It shouldn’t come as a surprise to fantasy managers that Clayton Kershaw is having a stellar fantasy season. However, it will come as a surprise that he has managed to stay healthy so far, going 9-4 with a 2.72 ERA, 1.10 WHIP, and 28.5% strikeout rate in 15 starts and 89 1/3 innings pitched. Considering these stats and a 30.6% CSW%, should fantasy managers have any concerns about Kershaw other than injury?

Kershaw’s off-speed pitches have been strikeout machines once again this season with a 22.2% swinging-strike rate on his slider and a 17.6% swinging-strike rate on his curveball. However, like Morton, Kershaw’s fastball has lived in the zone but hasn’t been particularly effective. He has allowed a .315 batting average against and .468 slugging percentage against with the pitch.

Clayton Kershaw, Nasty Sliders. 😨 pic.twitter.com/OZq3momFIj

— Rob Friedman (@PitchingNinja) June 21, 2023

Overall, there is some room for potential regression for Kershaw based on his fastball, but it isn’t enough for concern. His 3.51 xERA and 3.38 SIERA are higher than his current ERA but are still good marks. He should continue to rack up strikeouts with his slider and curveball either way.

At this point, injury is the only main concern, as Kershaw has not pitched more than 126 innings since 2019. Conservative fantasy managers may feel compelled to try to sell him, but I would rather hold onto him at this time given how volatile the pitching landscape has been.

CSW% Duds for Fantasy Baseball

All stats are current as of Sunday morning, June 18, 2023.

Cristian Javier, Houston Astros

7-1, 3.25 ERA, 1.12 WHIP, 25.3% CSW%

Cristian Javier has established himself as a solid fantasy starter over the course of his young career and has pitched well in 2023. His 7-1 record, 3.25 ERA, and 1.12 WHIP are what fantasy managers have come to expect. What hasn’t been expected is his 22.9% strikeout rate and 25.3% CSW% compared to 29.2% and 27.3% career averages. What is going on under the hood and should fantasy managers be concerned?

Javier has managed to be a dominant strikeout pitcher despite relying mainly on two pitches, his fastball and slider. That has remained the same this season, with 59% and 31.6% usage, respectively. Looking into his fastball, the velocity has been down about one MPH in 2023 compared to 2022 and the spin rate is down about 100 RPM. However, Javier has still worked with the pitch in the top of the zone and has a respectable 12.4% swinging-rate rate with the pitch compared to 13.3% in 2022.

The main culprit in the strikeout drop has been the slider. He has also seen a spin rate decrease on this pitch, leading to about two fewer inches of horizontal break. He has also failed to locate the pitch, leaving it primarily in the middle of the plate, rather than painting the outside corner for right-handed hitters like he did in 2022. Javier’s realized and expected results on the pitch have been surprisingly good, but his swinging-strike rate on the pitch has dropped from 16.9% to 11.1%.

Two-pitch starters always have less room for error since they have less to fall back on. Javier has gotten good overall results so far, but his CSW%, 4.19 xERA, and 4.48 SIERA suggest that he has gotten lucky. His slider’s decreased movement and lack of location haven’t come back to bite him yet, but I worry that they will over time. As such, I consider Javier to be a second-half sell-high candidate.

Taijuan Walker, Philadelphia Phillies

8-3, 4.10 ERA, 1.24 WHIP, 25.9% CSW%

Taijuan Walker has had a rollercoaster of a first season with the Phillies, going 8-3 with a 4.10 ERA and 1.24 WHIP. He has never been much of a strikeout pitcher and his 20.7% strikeout rate is in line with that, but his 25.9% CSW% is his lowest since 2019. What should fantasy managers make of his first half and what can they expect in the second half?

Walker’s approach has changed this season to heavily favor groundball-inducing pitches. He has primarily thrown a split-finger fastball and sinker over his four-seam fastball, which is the first time he’s implemented such a pitch mix. Consequently, he has allowed a lot of contact at 80.4%, which means he has had fewer opportunities for strikeouts.

Pitching to contact can be a recipe for success if done correctly, although Walker has had mixed results. He hasn’t always located those pitches in the bottom of the zone, leading to an overall launch angle of 9.4 degrees. This isn’t awful, but it is higher than expected for such an approach. He has allowed mediocre hard contact, with exit velocities and hard-hit rates in the 58th and 37th percentiles of baseball.

Walker has experienced both strong streaks and stretches of struggle this season, which has made it tough for fantasy managers to trust him. He doesn’t have overpowering stuff, so he really needs to keep the ball on the ground in order to be successful. I don’t think Walker has underperformed fantasy expectations this season and think that, despite the inconsistency, he should be a useful back-of-the-rotation starter for the second half of the season.

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