2020 Review: Hitter SwStk% Improvers

Let’s continue on with our look at the plate discipline metrics by moving onto swinging strike percentage (SwStk%). With a strong correlation of 0.77 (qualified batters from 2015-2019), SwStk% is a good proxy for strikeout rate and the two will usually move in the same direction. Because SwStk% uses a denominator of total pitches, versus K%’s use of plate appearances as its denominator, it takes far less time for SwStk% to become meaningful. As such, the value of the metric increases in a shortened season like 2020. So let’s review the 2020 batter SwStk% improvers.

Of the 18 hitters who improved their SwStk% by at least three percentage points, a whopping 16 of them also reduced their strikeout rates. The two whose strikeout rates actually increased only did so by a marginal degree.

There are a bunch of names that also appeared on the Z-Contact% and/or the O-Swing% improvers lists, so I’ll avoid repeating myself by skipping those players.

Tyler O’Neill had a real opportunity to earn an every day job with the Cardinals and ended up improving some important offensive skills. Though his whole MLB career now consists of three small sample size stints, he significantly improved upon his ability to make contact and also raised his walk rate along with it. All the extra contact ended up not mattering though, as his BABIP plummeted below .200. That’s a difficult hole to pull out of! While the BABIP should certainly rebound somewhat, he really needs to get that ISO over .200 and HR/FB rate into the 20% range to prove worthy of a starting job.

Will Smith was bombing during his 2019 debut and actually did so with a single digit SwStk%, which was overshadowed by a 26.5% strikeout rate, suggesting major passivity. This year, he improved his SwStk% to an elite level you don’t expect to see from a power hitter, and his strikeout rate dropped along with it. While his ISO unsurprisingly declined from its perch over .300, it still remained top notch, and his overall bucket of skills were quite impressive. He has recorded more than 400 plate appearances just once in his professional career, so we’ll see how he holds up over a full season. Obviously to be a top catcher, he’ll need 350 or so plate appearances at the very least just to give him any chance.

Yandy Diaz on another list of mine?! Man, if only some of those additional balls in play would be in the air, he would be golden.

Ramon Laureano’s SwStk% dropped into single digits for the first time, but he was one of just two on this list of 18 whose strikeout rate actually increased. Looking at the rest of his plate discipline metrics, we learn that he simply swung less often this year and in turn got called out on strikes at a career high rate, well above the league average. That seems fixable, so focus more on the SwStk% improvement. The real disappointment here was the drop in power and BABIP, making him pretty much worthless in shallow mixed leagues. This all smells like small sample randomness to me, so an opportunity to buy him at a discount next season should be taken advantage of.

An improved SwStk% and strikeout rate was much needed for Brandon Lowe, so he didn’t need to heavily rely upon a .377 BABIP to be valuable offensively. He delivered and even did so while raising his ISO and HR/FB rate, which is a great sign. He looks like the real deal and his miserable postseason might help to deflate his price next year.

It’s still hard for me to believe that Lourdes Gurriel Jr. is showing so much more power than he ever did in the minors, but he’s now done it over 771 at-bats, which is enough to take him seriously. He swings a lot, so a high SwStk% isn’t as scary as it might be for most other hitters, as it merely means a low walk rate, but not such a terrible strikeout rate. This year, his SwStk% and strikeout rate rebounded back toward his 2018 debut levels after both stepping backwards in 2019.

Jonathan Schoop is similar to Guerriel Jr. in that he swings frequently, so always posts SwStk% much higher than you would expect given his reasonable strikeout rates. His SwStk% marks have jumped around in the mid-to-high teens throughout his career and he was coming off one of the worst SwStk%/K% combinations of his career in 2019, making his 2020 improvements look like a real step forward, when they weren’t. With no speed, he will continue to remain a risky, low upside play almost solely dependent on his home run total.

Well sure, it wasn’t enough for Fernando Tatis Jr. to post skills en route to a ridiculous .398 wOBA during his 2019 debut, now he has to greatly improve those skills and confirm that he’s one of the brightest young stars in baseball. While his 2019 SwStk% was a bit high, it wasn’t alarming. This year, he brought his SwStk% and K% down to just above league average levels, which is a big move for someone with his power and speed. There’s little here to even nitpick now (the LD% was low in 2020, that’s about it), as this is a serious contender for most exciting underlying skills package in baseball.

It’s just incredible that Freddie Freeman ended up posting the highest wOBA of his career after his bout with COVID-19, in which we know he was symptomatic. His SwStk% dropped into single digits for the first time, while his K% fell to a career low, and the first time it dipped below 18%. Just amazing. His batted ball distribution heavy on line drives and light on pop-ups continues to be drool-worthy.