2020 Review: Hitter O-Swing% Improvers

The Plate Discipline stat section provides us with a lot of “underlying skill” information. Since these metrics use a denominator that grows more quickly than more traditional metrics such as strikeout and walk rates, they are more useful over small sample sizes, especially after a short season. So let’s now move on to hitter O-Swing% to learn which hitters reduced their swing rate on pitches outside the strike zone and which swung more often at such pitches. Since 2019, O-Swing% had about a -0.74 correlation with walk rate, so it’s clearly that holding back on swinging on pitches outside the zone is an excellent indicator of plate patience and current/future walk rate.

O-Swing% Improvers
Name 2019 BB% 2020 BB% BB% Diff 2019 O-Swing% 2020 O-Swing% O-Swing% Diff
Jacob Stallings 7.6% 10.5% 2.9% 38.0% 23.9% -14.1%
Freddy Galvis 4.8% 8.2% 3.4% 40.2% 28.0% -12.2%
Raimel Tapia 4.7% 6.8% 2.1% 43.5% 32.3% -11.2%
Giovanny Urshela 5.3% 10.3% 5.0% 41.8% 30.8% -11.0%
Christian Yelich 13.8% 18.6% 4.8% 30.6% 20.3% -10.3%
Mauricio Dubon 4.5% 8.5% 4.0% 46.2% 36.5% -9.7%
Corey Dickerson 5.7% 7.1% 1.4% 46.2% 36.5% -9.7%
Gleyber Torres 7.9% 13.8% 5.9% 35.1% 25.6% -9.5%
Kevin Kiermaier 5.4% 12.6% 7.2% 37.9% 28.6% -9.3%
Jose Iglesias 3.8% 2.0% -1.8% 46.7% 37.7% -9.0%

I was a semi-fan of Jacob Stallings heading into the season as a super cheap catcher who wouldn’t kill you and had the potential to actually add some value. Unfortunately, he simply didn’t get the playing time and his strikeout rate shot up. The sample sizes in his 2019 and 2020 metrics are rather small, but it is nice to see that huge reduction in O-Swing%. Unless the Pirates go out and get a clear alternative, I think he makes one of your best end-game catcher options again next year.

There’s Raimel Tapia again, who appeared in Monday’s Z-Contact% improvers list as well. Making better contact on pitches inside the strike zone and cutting down on your swings outside the strike zone is exactly the kind of improvements you want to see from a young player. Depending on his playing time outlook next year, he could be a solid target with profit potential, though be aware that any rebound in power could be coupled with a regression in his BABIP and resulting batting average.

Giovanny Urshela is another who made both the Z-Contact% improvers and this list. It’s a veddy good thing.

It was a surprisingly disappointing season for Christian Yelich, whose strikeout rate skyrocketed to just above 30%, after never being above 21% since his 2013 debut. One of the bright spots was increased passivity, as he posted a career low O-Swing%, which is excellent, but also posted a career low Z-Swing%, which just leads to more called strikes. One major question for fantasy owners is about the steals, as he was coming off a career best 30 swipes in 2019, but stole just four this year. Extrapolating those four steals this year to the same number of plate appearances as 2019, you end up with just 9. Some of that undoubtedly has to do with him simply reaching base at the lowest rate of his career. But if Yelich is no longer a double digit stolen base threat, or even just a low teens threat as opposed to 20+, his fantasy value take a reasonable hit. I think that would be my biggest question when trying to determine whether Yelich will be a bargain at drafts next year coming off a disappointing 2020 that fantasy owners might overreact to.

With the promise of some power and speed, Mauricio Dubon was an interesting sleeper. Although he didn’t quite get the playing time necessary to make him a shallow mixed league asset, he was on a 14 home run, seven steal pace over 600 plate appearances, which is more or less in line with reasonable expectations. That he nearly doubled his walk rate thanks to cutting down his O-Swing% is a good thing and led to additional stolen base opportunities, though he didn’t actually take advantage of those. This is a very decent skill set that will likely get overlooked, but a full-time job out of Spring training could make him a nice cheap target in drafts.

After five straight seasons with an O-Swing% over 40%, Corey Dickerson finally pushed that rate down below that plateau and recorded a new career best. Unsurprisingly, his walk rate rose to its highest level since 2014. Unfortunately, everything else took a hit, including his BABIP and ISO, both of which fell to career lows. So despite the jump in walk rate and even reduction in strikeout rate, his wOBA set a new career low and he failed to do much for fantasy owners. He’ll probably rebound somewhat next year, but his value is limited to deep mixed and NL-Only leagues.

It wasn’t all bad for Gleyber Torres! In fact, his Plate Discipline metrics look quite good, and his walk rate nearly doubled, jumping into double digits for the first time, while his strikeout rate slipped below 20%, marking the second straight season of improvement. The power was MIA, but everything else makes it look like a growth season, or a growth 160 plate appearances. I have felt that Torres had been overvalued in the past, but this might finally make him fairly priced and I’m buying a full rebound.

For the first time, Kevin Kiermaier’s walk rate shot into double digits, thanks in part to a strong improvement in O-Swing%. It didn’t actually lead to better overall offense though, as his .301 wOBA was below his .310 career mark. Speculation is that Kiermaier is a candidate to be traded, and given his still elite defense, you have to think he would remain a full-timer, on the strong side of a platoon, at the very least.

Who projected Jose Iglesias for a .407 wOBA?! Amazingly, he ranked fifth in baseball in doubles, driving a spike in ISO to the highest mark of his career. Amazingly, he did this while rarely walking, but also striking out infrequently. His apparent improvement in O-Swing% was really just the result of a spike in the rate in 2019 that was out of line with his history. So this year was merely a rebound back to pre-2019 levels. The funny thing is that his walk rate was actually higher in 2019, which is hilarious considering that walk rate was only 3.8% to begin with. His 2020 walk rate of 2% was the lowest of his career, which you would hope, but it wasn’t that much worse than his career 4.4% mark. Since he remains above average defensively and has been adequate offensively before 2020, he should remain the Orioles’ starting shortstop and continue to bore fantasy owners hoping all those balls in play continue to find holes.

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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Joe Wilkeymember
1 year ago

Yelich is an interesting case. His Zone% was only 36%, which was 3rd lowest among all qualifiers in 2020. His Z-Swing% was 12th lowest, O-Swing% was 7th lowest, which resulted in the 2nd lowest Swing% among all qualifiers. However, if we add up the times he swung in the zone and took a pitch out of the zone (a rough measure of “making the right decision”), this accounted for 72.64% of the pitches he saw, with league average being 68.74%. That is 18th best out 142 qualifiers. Most of the guys in the low Zone% group are either guys who swing at everything (Eddie Rosario/Luis Robert types) or really good hitters (Bryce Harper/Juan Soto types). Gleyber has a fairly similar profile as well, but I think his K% should be more in the vicinity of Yelich, but maybe not quite as high considering his higher contact rate.

I wouldn’t count on Dubon’s BB% staying that high. He still has an above average Zone%, an above average O-Swing%, and an above average Contact%. While the decrease is nice, I doubt the walk rate will stay that high. Same with Dickerson, only I expect his K% to jump too, considering his <80% Z-Contact%.

Jose Iglesias, part of the Orioles apparent approach of "swing at everything". Using the "right decision" metric, the Orioles were one of two teams to make the right decision less than 2/3 of the time, along with the White Sox. There is no way Iglesias's BABIP of .407 lasts, but it may not be as far off as you think (lots of LD and GB, plus relatively good speed), and those K% and BB% are real, for better or worse.