Starting Pitcher GB% Decliners — Apr 22, 2021

Yesterday, I listed and discussed the starting pitchers whose GB% marks of risen by at least 10% versus last season. The caveats here were — even though batted ball profiles stabilize more quickly than most other underlying metrics, the sample size still remains small, and an increased GB% isn’t necessarily “good”, but will likely change the shape of the pitcher’s performance and results. Let’s now move on to the GB% decliners and review those whose marks have declined by at least 10%.

GB% Decliners
Name 2020 GB% 2021 GB% Diff
Jake Arrieta 51.8% 31.8% -20.0%
Max Scherzer 33.0% 14.3% -18.7%
Zack Wheeler 55.9% 38.1% -17.8%
Jacob deGrom 42.5% 26.5% -16.0%
Yu Darvish 43.2% 30.0% -13.2%
Yusei Kikuchi 52.0% 39.6% -12.4%
Jordan Lyles 39.9% 28.6% -11.3%
Sean Manaea 50.3% 40.0% -10.3%

It’s likely that Arrieta’s early season strong surface results, including a sub-3.00 ERA, have resulted in many pickups throughout the fantasy land. This is a classic mistake, as ERA means little, with limited predictive value, over such a small number of innings. Instead, note that his underlying skills are essentially the same as the previous two seasons, with almost identically poor SIERA marks. In addition, his GB% has plummeted, while his FB% has skyrocketed to what would be the highest rate of his career. For a pitcher who a below average strikeout rate, that could potentially mean tons of home runs. Even in an NL-Only league, give me a middle reliever instead.

Holy guacamole, I don’t think I’ve ever seen such extreme GB%/FB% splits by a starting pitcher, or perhaps any pitcher, than what Max Scherzer has posted so far! Along with his tiny 14.3% GB%, he sports an extreme 64.3% FB%. His fastball velocity is down to what would be a career low, but that hasn’t affected his ability to generate swings and misses or strike batters out. Still, regardless of what the results have been so far, I’m curious where this goes from here. All those fly balls aren’t so bad when you’re striking out over 30% of batters, but will the velocity decline eventually affect him?

Last season, Zack Wheeler suddenly became a ground ball pitcher. That didn’t last very long, as he’s immediately returned to career averages. Like I mentioned for some pitchers yesterday, the decline in GB% isn’t totally real, as his LD% is inflated, and moving forward, a bunch of those liners are going to likely become grounders and move his batted ball profile right toward his career marks. He’s throwing his slider more than ever before at the expense of his sinker, which should be good for whiffs and strikeouts. However, his SwStk% is unchanged from last year and basically in line with his 2018-present marks, which is surprising. His strikeout rate is indeed up, but not because of swings and misses, which is what the slider typically induces. Weird.

I guess Jacob deGrom wasn’t happy with is performance just yet, so this year he has decided to experiment as an extreme fly baller. Since he strikes out so many hitters, the increase in home runs allowed shouldn’t have a significant impact, but his BABIP should benefit. Is that 23.2% SwStk% a typo? Oh, and someone please tell him that fastball velocity is supposed to decline with age, not increase.

Yu Darvish is yet another high strikeout pitcher allowing more flies than ever. I wonder if there’s anything to this in that all these pitchers are figuring out that the high strikeout/high fly ball approach is optimal (I don’t know if that’s true). He’s now throwing his slider 56% of the time, which is insane. It’s become more of a fly ball pitch this year, but the other driver is a four-seamer that hasn’t induced a grounder yet! It owns a 66.7% FB% and 33.3% LD%. I’ve never seen that before.

After becoming a ground ball pitcher last year amidst a spike in fastball velocity, Yusei Kikuchi has maintained those velocity gains, but reverted back to his 2019 batted ball profile. He looks to have resolved his control issues, but is once again dramatically underperforming his SIERA.

Jordan Lyles has proven that last year’s strikeout rate decline was the fluke, but now he has become an extreme fly ball pitcher and he doesn’t exactly have the strikeout rate to justify it. He probably wasn’t on many fantasy radars to begin with, but he won’t end up on mine for as long as he continues allowing so many flies without the strikeout rate to limit the home runs.

Thanks to improved velocity, Sean Manaea’s strikeout rate has risen, while his SwStk% has jumped to the highest mark of his career. While his GB% has declined, it’s merely back in line with his pre-2020 seasons, as last year marked his highest GB% ever and the only time his FB% sat below 30%. I’d still rather see the higher ground ball version given his lowish strikeout rate, but he does play in the right home park to allow more flies.





Mike Podhorzer is the 2015 Fantasy Sports Writers Association Baseball Writer of the Year. He produces player projections using his own forecasting system and is the author of the eBook Projecting X 2.0: How to Forecast Baseball Player Performance, which teaches you how to project players yourself. His projections helped him win the inaugural 2013 Tout Wars mixed draft league. Follow Mike on Twitter @MikePodhorzer and contact him via email.

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rustydude
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rustydude

Seems like most of the pitchers on this list have reasonably good command and may be intentionally choosing to throw higher in the zone or throw pitches with less down break, as the author infers.