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

September 12, 2022

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

Welcome back to fantasy baseball and 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 an 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 in the season.  

Fantasy managers cannot afford to make start-vs.-sit mistakes in the final few weeks, so overall performance metrics can 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, September 11, 2022.

Spencer Strider: Atlanta Braves
10-4, 2.69 ERA, 0.97 WHIP, .231 wOBA

Spencer Strider started as a fantasy non-factor in the Braves' bullpen but has been an absolute stud since he joined the rotation at the end of May. The 23-year-old has compiled a stellar 2.69 ERA, 0.97 WHIP, and a ridiculous 38.1% strikeout rate. Consequently, his .231 wOBA is one of the best among starting pitchers.

While his strikeout numbers have been elite, Strider tends to throw a lot of pitches, which have led to some short starts. Do fantasy managers have anything to worry about for the end of the season?

Strider's performance as a starter has been extremely impressive, especially because he essentially relies on only two pitches. He has managed his high strikeout rate and 15.5% swinging-strike rate thanks to a 98.2-MPH fastball with a ton of spin and a hard slider. He has allowed weak contact when hitters have connected, with an exit velocity in the 70th percentile of baseball and a hard-hit rate in the 71st.

Strider's overall Statcast profile is stellar, except for his walk rate. His 8.5% walk rate certainly leaves something to be desired and eats up his pitch count, which already tends to be higher due to all of his strikeouts. This has led to some disappointing outings, but Strider's upside is too great to take any action on this.

Strider has proved to be a dangerous fantasy option with immense upside, and every player has the occasional off day or bad start. The fact that his wOBA has been so solid despite his walks is a testament to how well he has pitched. I see Strider as a must-start for the rest of the season, with the hope that he can avoid one of his short starts.

Zac Gallen: Arizona Diamondbacks
11-2, 2.42 ERA, 0.92 WHIP, .248 wOBA

Zac Gallen experienced multiple injuries in 2021 and saw his overall results regress in 2021. However, he has clearly bounced back this season with a 2.42 ERA, 0.92 WHIP, 25.6% strikeout rate, and .248 wOBA. How has Gallen done so well this season?

The simple explanation is that Gallen has more or less pitched like he had before he got hurt. He has given up slightly harder contact than 2019-2020, although still above average, but has lowered his launch angle to a career-low 10.3 degrees. He still relies primarily on his four-seamer at 48.1% but has gotten great results with it while also mixing in a curveball, changeup, and cutter.

He has taken relative steps forward in terms of limiting walks, as indicated by his wOBA. He has managed a career-low 6.7% walk rate, which has led to a career-low WHIP. He has also experienced a career-low BABIP at .235.

Gallen has returned to being a strong fantasy asset this season now that he's healthy. He has pitched with a high floor, has averaged almost six innings per start, and has been backed lately by a surprisingly hot offense. He will have some tough in-division matchups down the stretch, but his season-long success gives me trust in him.

wOBA Duds for Fantasy Baseball

All stats are current as of Sunday morning, September 11, 2022.

Lucas Giolito: Chicago White Sox
10-9, 5.18 ERA, 1.49 WHIP, .356 wOBA

Lucas Giolito has been a huge fantasy disappointment this season. Despite still being rostered in 90 percent of leagues, Giolito has one of baseball's highest wOBAs at .356. Fantasy managers have not given up on him, but is there too much at risk to trust him now?

There are a few underlying signs that Giolito has gotten unlucky this season. Despite a middling batted-ball profile (his exit velocity and hard-hit rate are in the 50th and 35th percentiles of baseball to go with a 13-degree launch angle), his BABIP is very high at .352. Further, his 4.26 xERA, 3.64 xFIP, and 3.78 SIERA all suggest that he has performed better than his peripherals and wOBA.

This is a good example of players' performance not aligning with their underlying metrics. Fantasy managers have trusted in Giolito throughout the season despite his performance, and while he may be a nice buy-low candidate for next season, I would hesitate to trust him in the fantasy playoffs.

Giolito will potentially face tough matchups at the Guardians, against the Guardians, at the Twins, and at the Padres. I would rather not have to rely on him than hope to see some positive regressions over the final month of the season.

Josiah Gray: Washington Nationals
7-9, 5.06 ERA, 1.37 WHIP, .355 wOBA

Josiah Gray was a highly-touted fantasy prospect but has not panned out in his first two seasons. He has managed a bloated 5.06 ERA, 1.37 WHIP, and .355 wOBA through his 25 starts with the Nationals this season. The 24-year-old is only rostered in 29 percent of leagues now, but what could fantasy managers in dynasty leagues expect from him in the future?

The two things that stand out for Gray are his launch angle and his lack of command. He hasn't given up particularly hard contact, but his 21.2-degree launch angle has led to a 50.8% flyball rate, a 19.6% HR/FB rate, and a 2.46 HR/9 rate.

Gray has walked too many hitters when he isn't giving up home runs. His 10.4% walk rate has led to a 4.10 BB/9 rate and has contributed to his high WHIP. The culprit behind both issues has been his four-seamer, as he has thrown it up in the zone but only in the zone 53.5% of the time and has a .290 batting average and .694 slugging percentage against.

Gray does have a three-pitch mix and his slider and curveball have been quite effective, but his fastball has gotten him into trouble. It does seem that Gray could use his skillset to become an effective pitcher, either by throwing his fastball lower in the zone or maybe by throwing the pitch less in general. Either way, I do not think that those adjustments will get figured out this season.

More Sabermetrics and Statcast Analysis