In terms of true talent, there are few players better than Aaron Judge. When he is on the field, he produces and produces big time. Since 2017 when he became a full time player, he’s 8th in the Majors in fWAR (18.9) despite being 96th (!!!) in plate appearances in that same time frame. 8th in fWAR! 96th in PA! That’s absurd! Anyway, it’s clear that health has been an issue for Judge. Since playing 155 games in 2017, when he was definitely hurt at the end of the year, he’s never played in more than 115 games, and just 28 in pandemic ball in 2020. So, like we said for Giancarlo Stanton, just being healthy could be his improvement. But that’s boring and a bit of a cop out, so let’s take a look at something else.
In 2017, Judge had an 18.7% walk rate. In 2018: 15.3. 2019: 14.3. 2020: 8.8%. Now, the normal pandemic baseball caveats, apply, but that’s a big plunge in a downward trend. Obviously, Judge was still productive even with a lower walk rate. He still managed a .369 OBP and had a towering .297 ISO (.521 SLG), to help make up a .375/139 wOBA/wRC+ combo. So what caused the lower walk rate? It’s kind of hard to tell, actually.
The first thing we’d want to look at is if he was striking out more, robbing himself of opportunities for walks. That’s out the door because his strikeout rate fell in 2020. His whiff rate also fell. He chased 1.2% more pitches outside of the zone, but that didn’t seem to be too detrimental, considering the drop in strikeouts. Judge even saw fewer first pitch strikes by 6% and swung at the first pitch 7.5% less often.
The “culprit,” if we can call it that, might in his contact rate. While his chase contact rate was essentially identical to 2019’s, his 2020 in-zone contact rate jumped up to a career high 80%, a high by almost a full 4% (2017, 76.8). So perhaps more contact on those pitches led to shorter at bats and fewer walks? Even that feels like a stretch.
One more angle I noticed was that the number of pitches he saw on the edge of the zone eked up to 42.7%, a full 1.1% higher than last year (full is doing lot of work there). Maybe some of those edge pitches are ones he’s making chase contact with, leading to fewer walks? Still not feeling very definitive.
Looking at his pitches faced data, one last thing jumped out and that was his performance against cutters. In 2019, he had a 33.3% whiff rate and 32.1% strikeout rate on the pitch, which he saw 7.1% of the time. In 2020, he saw the pitch less often–6.2%–but with more swing and miss: 36.4 whiff rate, 37.5 k-rate. Maybe these cutters, which tend to run out of the zone, that he was able to do damage on in 2019 (.438 wOBA) are ones that he missed in 2020 (.088 wOBA). But the 2020 sample is obviously quite small, so be mindful of that caveat.
It seems like Aaron Judge’s drop in walk rate can be explained by marginal differences and just some random baseball flukiness, highlighted more by the small sample of pandemic baseball. Regardless of the cause, I expect Judge’s walk rate to (all) rise in 2021 and for him to keep on raking. Hopefully, it’s for 150+ games.