Hitter Auto Out Percentage Regressors

Yesterday, I discussed the nine hitters whose Auto Out% (AO%) had improved most versus 2017. As a reminder, AO% is simply the sum of strikeouts and infield fly balls (aka, popups) divided by plate appearances. Let’s take a look at the hitters whose AO% has risen most dramatically versus last season.

Auto Out% Regressors
Name 2018 Auto Out% 2017 Auto Out% Diff
Gregory Polanco 26.4% 17.5% 8.9%
Eduardo Nunez 22.4% 13.8% 8.5%
Kyle Seager 25.4% 18.8% 6.7%
Eric Hosmer 23.3% 16.7% 6.7%
Billy Hamilton 29.5% 23.5% 6.0%
Jeimer Candelario 29.1% 23.2% 5.9%
Jordy Mercer 23.8% 18.1% 5.7%
Giancarlo Stanton 33.4% 27.7% 5.7%
Carlos Correa 26.0% 20.6% 5.4%

Introducing Gregory Polanco 2.0. Nearly every skill metric has changed dramatically this year and he deserves an entire article devoted to his season so far. So although his AO% has jumped, his wOBA is actually sitting at a career best thanks to the changes in his underlying skills. It’s too bad he has never shown BABIP talent and barely steals bases anymore.

Eduardo Nunez has played almost every day, but has done nothing with that playing time. He’s currently sitting with a career worst strikeout rate and his IFFB% has skyrocketed above 20%. When you already possess such limited power, you can’t afford to be giving away so many at bats. Worse yet, he’s swiped just four bases, so his one real expected contribution has been relatively non-existent.

I’ve always been a bit skeptical of Kyle Seager because he never really possessed a standout skill. His strikeout rate was always better than average, but he just failed to excite me. Sadly, that strikeout rate has spiked above 20% for the first time, while he’s hitting far more pop-ups. Last year’s fly ball rate surge was short-lived, so with fewer of his flies getting the opportunity to hop over the wall, his wOBA has sunk to a career low.

16.9%. That’s Eric Hosmer’s fly ball rate. ARE YOU KIDDING ME? Is he doing this just to spite those who may have suggested he hit more fly balls? You would never know his HR/FB rate is above 20% for the third straight season because all those grounders means he’s hit just 10 homers. I think it’s time we just acknowledge that he’s never going to get that grounder rate below 50%.

LOL, Billy Hamilton has hit more fly balls than Hosmer…like, way more. Unfortunately, his strikeout rate has risen for a third straight season to a career worst, and when you possess such little power, you end up with another sub-.300 wOBA. Along with the strikeouts are more pop-ups than ever before. It’s a good thing he’s such a strong fielder, as he would have found himself back in the minors if not.

So we’re comparing Jeimer Candelario’s AO% to just 142 plate appearances in 2017, but he’s been worse in both strikeouts and pop-ups. The good news is he’s showing improved plate patience and also pushed his ISO above .200. Furthermore, the high strikeout rate comes with just a 9.7% SwStk%, which is lower than you’d expect. I’m optimistic about his future.

How does Jordy Mercer keep a starting job every season?! He isn’t even strong defensively, sitting with a negative career UZR at shortstop.

We all think of Giancarlo Stanton as a slugger who strikes out a ton. But, he actually never struck out 30% of the time in a full season. His strikeout rates have always certainly been worse than average, but not outrageous, and perfectly acceptable for his power output. Now, his strikeout rate has creeped above 30%, and suddenly his walk rate has dipped into the high single digits. His performance would look even worse if it weren’t for an inflated .360 BABIP, which has no chance of being sustained.

Though Carlos Correa’s SwStk% remains in the high single digits and below his high set in 2016, his strikeout rate has jumped to its worst mark. Fortunately, his pop-up rate remains low. It’s still pretty amazing that he’s only 23.

We hoped you liked reading Hitter Auto Out Percentage Regressors by Mike Podhorzer!

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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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Cory Settoon

Not only has Nunez only swiped four bags, his BsR for the year is a -6.0

That’s around Smoak, Bour, and some catchers. I’m guessing the knee problem has more impact than first thought.