Statcast Pitcher Studs and Duds - Advanced Metrics Leaders for SIERA (Week 7)

May 9, 2023

Connelly Doan examines fantasy baseball pitcher risers and fallers, and whose SIERA could make them adds, drops, or trade targets for Week 7.

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. With just over a month of data, I think it's time to take a first look at one of my favorite advanced metrics; skill-interactive earned run average (SIERA).

SIERA is a great metric for capturing a pitcher's independent performance. It quantifies a pitcher's performance by trying to eliminate factors the pitcher can't control on their own. Fielding-independent pitching (FIP) is a stat that also attempts to do this, but unlike FIP, SIERA considers balls in play and adjusts for the type of ball in play. The formula can be found here for those who want to get into the nitty-gritty.

SIERA is a truer indicator of a pitcher's performance than ERA or FIP and can help predict future success or failure compared to a pitcher’s current ERA. It is one of a few great metrics for identifying potential buy-low and sell-high candidates, so this will hopefully be a helpful article for those of you taking a look!

SIERA Studs for Fantasy Baseball

All stats are current as of Sunday morning, May 7, 2023.

Zac Gallen, Arizona Diamondbacks

4-1, 2.53 ERA, 0.84 WHIP, 2.47 SIERA

Zac Gallen showed in 2022 why fantasy baseball players had high hopes for him, and he has continued that success this season. He has led the hot Diamondbacks with a stellar 2.53 ERA, 0.84 WHIP, and 35.2% strikeout rate in seven starts. Further, his 2.47 SIERA backs up everything he has done. Let's dig into his success.

First, Gallen has mixed pitches well with a good location. His batted-ball profile is middle-of-the-road, but he has done a good job working in the top of the zone with his four-seamer and in the bottom of the zone with his other pitches. As such, he has frequently avoided damaging contact.

Gallen's curveball specifically has been a filthy pitch. It brings a 12-6 profile with an above-average drop and a 21.5% swinging-strike rate. He has gotten just a 52.4% contract rate on the pitch overall and has had great success using it as a chase pitch, with a swing rate outside the zone of 35.7% and just a 30.4% contact rate on those swings.

PSA: Zac Gallen has the best curveball in baseball, and we will not be convinced otherwise.
pic.twitter.com/BOkeqFsLJR

— PHNX Diamondbacks (@PHNX_Dbacks) April 11, 2023

Overall, Gallen has continued to deliver as an above-average fantasy starter. His consistency has picked up right where it left off after 2022, and he should continue to see strikeout success thanks to his curveball. His ERA and SIERA align, further suggesting that he should continue to provide strong results.

Logan Webb, San Francisco Giants

2-5, 3.80 ERA, 1.11 WHIP, 3.09 SIERA

Logan Webb did not have the cleanest start to the season, and while he has gotten things back on track, his  2-5 record and 3.80 ERA were not exactly what fantasy managers had hoped for. The good news is that his 3.09 SIERA is one of the lowest this season among qualified starters. Does this mean that fantasy managers should expect some positive regression?

Fortunately, there is one big identifiable outlier right off the bat for Webb; the high home run count. Webb's batted-ball profile is very similar to what it has been his entire career, with slightly harder contact allowed but on the ground with a 4.6-degree launch angle. However, Webb's fly-ball rate of 28.9% is higher than his career mark of 22.5% and his HR/FB rate of 22.9% is much higher than his career mark of 12.1%.

Webb is a sinker-heavy pitcher and his batted-ball results and SIERA suggest that he has done a successful job of that, even though the numbers have not fleshed out that way to this point. This should give fantasy managers hope that things will start to work out in Webb's favor as he pitches more innings. I don't think fantasy managers would necessarily be willing to trade Webb, but he can still be considered a buy-low candidate at this time.

SIERA Duds for Fantasy Baseball

All stats are current as of Sunday morning, May 7, 2023.

Alek Manoah, Toronto Blue Jays

1-2, 4.71 ERA, 1.65 WHIP, 5.41 SIERA

Our duds this week will be a pair of rotation mates. Alek Manoah got off to a very slow start to the season and has a 4.71 ERA, 1.65 WHIP, and 18.1% strikeout rate to show for it. Even worse, his 5.41 SIERA is one of the highest among qualified starters and is a good deal higher than his ERA. What should fantasy managers make of this?

The thing that stands out to me is Manoah's poor pitch location. His fastballs and slider have been left up in the zone, leading to harder contact than he typically allows with a higher rate of line drives and fly balls. As I have mentioned in previous articles, allowing a combination of hard contact in the air is not a successful combination for pitchers, and Manoah's SIERA has reflected that.

Further, even though Manoah has managed a 2.12 ERA over his last three starts, he has still given up hard contact at an average of 89 MPH and has a 4.43 SIERA over those starts.

It is still early in the season with plenty of time left for Manoah to get things back on track. As such, I would look to buy low on him at this time, but I don't see a ton under the hood to give me confidence in him. The price would have to be pretty favorable for me to pull the trigger.

Chris Bassitt, Toronto Blue Jays

4-2, 4.28 ERA, 1.23 WHIP, 5.20 SIERA

Chris Bassitt has found relatively more success than his teammate with a 4.28 ERA, 1.23 WHIP, and 19.6% strikeout rate. However, his 5.20 SIERA is only slightly better than Manoah's. Fantasy managers likely haven't been worrying given his overall results, but should they be?

This case is not as clear as Manoah's. Unlike Manoah, Bassitt has done a good job limiting hard contact this season, with an exit velocity and hard-hit rate in the 83rd and 82nd percentile of baseball. He has clearly gotten lucky to some extent, as his .217 BABIP is much lower than his career mark of .278. As such, it makes sense that his SIERA would be worse than his ERA, but it's hard to point to something that suggests he will regress.

Bassitt's SIERA is quite high and is higher than his ERA, but there isn't a blatant culprit. His Statcast profile in general is not great, but his batted-ball profile has been pretty good. He has definitely gotten lucky on balls in play, but there isn't anything to suggest that that good luck will stop. At this point, I am more confident in Bassitt producing decent results than Manoah.

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