PLV Weekly: Analyzing Swing Decisions with PLV

Using PLV to see who's making good and bad swing decisions in 2024.

We’re back with another week of the PLV report. This series will use the PLV metrics to contextualize player performance. This early in the season, we’ll be using our PLV model (Nick’s primer on PLV from last year can be found here) to dig deep on hitter performance. Are they swinging at the “right” pitches (Decision Value)? Are they making more or less contact than expected (Contact Ability) or regressing in how hard they’re hitting the ball (Power)? Note that PLV Hitter metrics are normalized to 100 (with 15 points being a standard deviation above or below that) and Decision Value (DV) has been further broken down into oDV and zDV, referring to swing decisions outside the zone and inside the zone, respectively.

We’re slowly getting enough sample to extract some signal from the noise, with those thresholds roughly starting at 400 pitches faced for DV, 200 swings for Contact Ability, and 75 BBE for Power. In addition, swing aggression begins to stabilize at ~25 pitches, so most regulars have already told us how aggressive they are at the plate. Let’s check on a few players who have either met those thresholds or who are far enough away from average (or from their performance last year) that I’m willing to take their metrics seriously.

Note: PLV metrics listed are current through Monday, April, 22nd.


Elly De La Cruz 


One of the biggest questions about De La Cruz coming into 2024 was if he could maintain his gains in Decision Value from the end of his rookie season. If he could continue making even league-average swing decisions, that would allow the rest of his very loud tools to play up during games.

The early returns from 2024 validate those late-season improvements: Elly De La Cruz is no longer terrible (or even bad!) at making swing decisions. This most notably shows up in his 13.6% walk rate that is substantially better than his 8.2% in 2023. When you also consider that he’s providing league-average Contact Ability and is folding in even more Power than last year, we’re looking at the ideal version of De La Cruz at the plate. Oh, and he also leads the league in Stolen Bases.


Aaron Judge


Aaron Judge is slumping, which is cause for concern for fantasy managers and Yankees fans everywhere. The upside of that statement is that an Aaron Judge “slump” is still someone with a 101 wRC+. Even with that very high floor, I have optimism that he’ll get back to his all-conquering ways since a peek at his underlying stats shows that the rumors of his demise are greatly exaggerated.

His Decision Value is down slightly from last year (126 this year vs 135 last year), but what’s interesting is how his approach is different this year: While running roughly the same Swing Aggression, he’s increased his inside-the-zone Decision Value (zDV) by 10 points while dropping 10 points in oDV. Considering his overall Swing% is 4% lower this year, that tells me that Judge is doing a better job of laying off the pitches that are least useful to him in the zone. Between that and a substantially improved Contact Ability (92 vs 72 last year), Judge has a lot working for him once he inevitably finds his swing and taps into his 80-grade power stroke.


Jorge Soler


It sounds counterintuitive, but most hitters add value by swinging less often, not more. This was shown by Tom Tango, MLB Advanced Media’s Senior Data Architect in this chart, where only a few dozen players with >1000PAs even have positive value when they swing. Making contact with a ball that could be going 100mph or moving 20″ away from you is hard, and having that contact drop for a hit is even harder. This is why I always keep an eye out for players who swing more often while maintaining or improving their Decision Value. Jorge Soler happens to be one of those players.

Soler went from swinging 2.9% less often than expected last year, to 1.6% more often than expected this year, which happens often enough. He happened to do it while maintaining his Decision Value, because he improved his zDV by nearly 20 points without a major drop to his oDV. It’s not quite the ideal change of “swing in the zone more while chasing less”, but it’s pretty close; his O-Swing% has only gone up 0.8%, while his Z-Swing% jumped by over 6%. This change has allowed Soler to maintain his CSW, even while he’s whiffing more than last year. This is a “floor-raising” move for a hitter: he’s no longer reliant on making a ton of hard contact to thrive since he has a better K% and BB% foundation (though I’m sure the Giants wouldn’t mind if he started making hard contact again).


Randy Arozarena


It hasn’t been a great start to 2024 for Arozarena (38 wRC+ through 95 PA), and I’m worried that this isn’t just a slump. He’s been more patient this season (-6.2% Swing Aggression, vs -4% last year), which has benefited his oDV at the expense of his zDV. That plummeting of his zDV (81 this season vs 106 last season) has tanked his ability to make contact. He’s dropped his O-Swing% to a career-low 24.5%, but I’m worried that he’s letting too many hittable pitches go by, which is a problem when his Zone rate is nearly 5% higher this year.

Arozarena has historically been a very good hitter, the season is still fairly young, and the Rays are a smart org. Hopefully, he can get back to the less passive approach that has benefitted him in the past, but I’d be keeping an eye on his Decision Value, especially his zDV. If that doesn’t start to right itself soon, these first few weeks may only be the start of a rough season for him.


Ian Happ


Is Ian Happ a mini Aaron Judge? I doubt many people are saying that, but he has made a similar trade of boosting his in-zone decision-making at the expense of his out-of-zone decisions. Happ has always made good decisions at the plate, but the shape of those decisions is much more balanced this season, with a zDV of 114 and an oDV of 113.

He’s been slightly more aggressive this season, and that change is almost entirely in the zone (2.5% higher Z-Swing%). This has paid dividends, as he is running the lowest SwStr% & K% of his career (9.9% and 21.6%, respectively) and has his 2nd highest BB% (14.8%). Happ’s decisions have made him a high-floor player in the past, and this year appears no different. If he can get back to the league-average Power he showed last year, he’ll be a very useful player at the top of the Cubs’ lineup.


Jonathan India


Jonathan India has simply stopped swinging. Already one of the more passive hitters in 2023 (-9.7% Swing Aggression), India has taken that to another level this year, swinging at pitches 15.7% less often than expected, based on the quality of the pitches. The out-of-zone benefits to this are obvious: he has the second-lowest O-Swing% in baseball (18.5%, just behind Juan Soto), and he’s nearly doubled his walk rate (16.3%, vs 9.8% last year).

The problem comes from how this has affected the hittable pitches he does see. Similar to Arozarena above, India is letting a lot of hittable pitches go by. This isn’t as much of a problem for India, since he’s is making exemplary Contact, but he almost has to make a ton of contact for this approach to work. Pitchers will get wise to him letting nearly half of all the pitches he sees in the zone go by and will start to pound the zone more, especially if his soft-hitting ways this season continue. I believe India has underperformed so far, but he needs to find his power stroke before his patience becomes an anchor that sinks his season.


Teoscar Hernández


Going to the Dodgers has revolutionized Hernández’s approach at the plate. He’s dialed down his Swing Aggression by almost 3%, fueled by a huge drop in how often he was chasing. His O-Swing rate has seen an 8.4% drop since last year. He isn’t just stopping indiscriminately, either, as his oDV has risen 20 points since last year, showing that he’s laying off the right pitches outside of the zone. That’s quite the feat to pull while also maintaining a stellar zDV. Hernández will always have some swing-and-miss to his game, but this new approach with Los Angeles is raising his floor by making the pitches he swings at easier to hit and hit hard.


Bryan Reynolds


Reynolds has undergone one of the bigger Swing Aggression changes from 2023-2024, going from +2.3% last year to -4.4% this year. This has had a trickle-down effect across his underlying metrics and results. Easily the biggest boon is a 16% walk rate, which is 3.5% higher than any other professional season in his career (including the minors). Reynolds is taking free bases at a rate that was previously unheard of for him, driven by a minor (1.3%) decrease in O-Swing%. It’s not all positive, though, as Reynolds is also swinging 7.5% less often at pitches in the zone (which is why his zDV has dropped to 78 this year, after he had 112 last year). This hasn’t hurt his strikeouts (his K% is at a career-low 17.9%), though those may be something to monitor going forward as he also has a career-low 69.7% Contact rate and career-high 27.9% CSW. His contact rate and CSW are mirrored by his zDV, due to swinging at tougher pitches to hit or not swinging at pitches in the zone at all.


Pete Alonso


Pete Alonso’s game is launching bombs, something he’s done about once every 3-4 games for his entire career. It makes sense to not care if he’s swinging at the “right” pitch when he can so frequently put a “wrong” pitch into the outfield bleachers. Alonso had struck a great balance last year, hitting for ridiculous power while keeping a positive Decision Value and a patient approach. Thus far in 2024, he has reverted back to his 2022 Decision Values (though now he’s extra passive, instead of slightly aggressive like 2022). That doesn’t sound so bad on the surface: he ran a 141 wRC+ in 2022, but he relied on his otherworldly batted ball contact (and the frequency of it) to help him succeed. If his quality of contact starts to dwindle (0.329 xwOBA this year, vs. 0.368 in 2023 and 0.353 in 2022), he’ll need to make more contact to counteract a subpar approach. If he stays passive but those takes aren’t helping him, he may end up leaving batted ball value on the table by swinging less.

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