Statcast Pitcher Studs and Duds - Advanced Metrics Leaders for wOBA (Week 23)

August 28, 2023

Connelly Doan examines fantasy baseball pitcher risers and fallers, and whose wOBA could make them adds, drops, or trade targets for Week 23.

Welcome back to another edition of RotoBaller’s Statcast Pitcher Studs and Duds article series! Each week, I 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. This week, I will focus on a stat that describes how pitchers have performed overall: weighted on-base average (wOBA).

wOBA is used to establish the value a player brings per plate appearance using unintentional walks, base hits, and hit-by-pitches. It is scaled like on-base percentage. It is a nice catch-all metric to gauge player performance. While I have looked at expected wOBA throughout this season, how a pitcher should have performed is not as important as how they have actually performed at this point. 

Fantasy managers cannot afford to make start/sit mistakes in the final few weeks of the season, so overall performance metrics can be very useful. To that end, let's take a closer look at wOBA!

wOBA Studs for Fantasy Baseball

All stats are current as of Sunday morning, August 27, 2023.

Corbin Burnes, Milwaukee Brewers

9-6, 3.65 ERA, .267 wOBA

Corbin Burnes is having a fine season overall, going 9-6 with a 3.65 ERA, 1.08 WHIP, and 24.9% strikeout rate in 26 starts. However, this has not been nearly what fantasy managers were expecting from one of the top picks this season. The good news is that Burnes' .267 wOBA is the lowest among qualified starters. Fantasy managers are likely all-in on Burnes at this point, but what can they expect from him?

There are a number of underlying metrics to support Burnes' strong wOBA. He has enjoyed a strong batted-ball profile once again, avoiding hard contact with a .238 BABIP. Oddly, he has a 4.15 SIERA, but his 3.38 xERA and wOBA suggest that he has pitched well overall this season.

The most noticeable area of decline for Burnes has been the strikeouts. Burnes' arsenal has been similar to previous seasons, and there haven't been any overall dips in velocity or spin rates. However, his overall swinging-strike rate has fallen to a career-low 12.1% compared to a 14.9% career mark. This may have to do with a lack of chases, as Burnes currently has his lowest chase rate since 2018.

Overall, Burnes has been frustrating for fantasy managers this season but he hasn't been a bad fantasy option. A number of his metrics suggest he has gotten unlucky, but the lack of strikeouts has been the biggest issue. Burnes will be an interesting pitcher to discuss for next season, but fantasy managers should lean on him for the rest of this season.

Eduardo Rodriguez, Detroit Tigers

9-7, 3.21 ERA, .277 wOBA

Eduardo Rodriguez has shown glimpses of being an impact fantasy starter throughout his career, but injuries have mainly prevented that from coming to fruition. While he has spent time on the injured list this season, everything seems to be clicking finally as Rodriguez has a 3.21 ERA, 1.11 WHIP, 24.3% strikeout rate, and .277 wOBA. Can fantasy managers expect the same from him for the rest of the season?

Part of Rodriguez's success could be due to an increased use of his changeup instead of his sinker. He relies heavily on his four-seamer and cutter, so the changeup provides a change of pace. This has yielded improved results overall, particularly in the strikeout department. This makes sense, as his changeup is one of his best swing-and-miss pitches with a 16.4% swinging-strike rate.

Eduardo Rodríguez, K'ing the Side. pic.twitter.com/QvW8mJl9LN

— Rob Friedman (@PitchingNinja) August 20, 2023

Rodriguez has also done a better job keeping runners off the basepaths. His 1.11 WHIP is much lower than his career 1.29 mark thanks to a career-low 6.5% walk rate. This, in combination with a career-low 9.2% HR/FB rate, has helped him avoid blowup outings, which is reflected in his almost six IP/GS.

Rodriguez may not be the flashiest fantasy option, but he has been a high-floor contributor when healthy. His updated pitch mix has led to more strikeouts and he has kept runners off the basepaths, leading to fewer runs scored. Given his performance, there is no reason to think he can't be a solid rotation piece for fantasy managers throughout the playoffs.

wOBA Duds for Fantasy Baseball

All stats are current as of Sunday morning, August 27, 2023.

Andrew Heaney, Texas Rangers

9-6, 4.34 ERA, .339 wOBA

Andrew Heaney has not been nearly as effective in his first season with the Rangers as he was last season with the Dodgers. While his 4.36 ERA, 1.36 WHIP, and 24.1% strikeout rate aren't bad, they are not nearly as stellar as his 2022 numbers. Further, his current .339 wOBA is one of the highest among qualified starters. Can fantasy managers hope for any better down the stretch?

There are a number of issues working against Heaney. One is he allows a lot of hard contact in the air. His 90.5 mph average exit velocity is in the 17th percentile of baseball. Combined with a 15.5-degree launch angle, Heaney has endured a lackluster 1.62 HR/9 rate.

The other issue is that he has had to deal with a lot of baserunners. Heaney's .296 BABIP is in line with his career average, but he has allowed a career-high 9.3% walk rate and a .440 expected slugging percentage that is in the bottom quarter of baseball.

All in all, Heaney's 2022 season seems to be a standout fluke compared to the rest of his career. As such, it is not all that surprising to see his disappointing regression this season. He has allowed too many baserunners with a lot of hard contact, which is not a recipe for success. He may have a great offense behind him, but I would avoid Heaney for the fantasy playoffs if possible.

Graham Ashcraft, Cincinnati Reds

7-8, 4.84 ERA, .351 wOBA

Graham Ashcraft poses a fantasy conundrum. He owns a poor 4.84 ERA, 1.38 WHIP, 17.3% strikeout rate, and .351 wOBA on the season. However, he has looked like a completely different pitcher in the second half, posting a 2.58 ERA and 1.05 WHIP in eight starts. Given his hot streak, should fantasy managers trust him down the stretch?

Ashcraft is mainly a two-pitch pitcher, relying on a cutter, a slider, and occasionally a sinker. I have mentioned the potential issues of two-pitch starters throughout this series, and they apply to Ashcraft as well. He has left his cutter in the middle of the plate too often, leading to a .357 wOBA against.

Further, Ashcraft's underlying numbers during his second-half surge leave plenty of questions. He has had a 17.8% HR/FB rate and a 4.48 SIERA during that stretch, suggesting things may have not fundamentally changed for him.

Ashcraft has gotten better results lately, but that doesn't necessarily mean he has made lasting changes to his game. There are a number of poor underlying metrics still present for him. It should make fantasy managers cautious, particularly because he pitches his home games in a hitter's park. I would not want to put my fantasy life in the hands of Ashcraft at this time.

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