a short ramble on hisanori yasuda's 2025 passive power outage
Before the start of the 2026 NPB season, Yakyu Cosmopolitan was kind enough to invite us to share our standings predictions. When coming up with predictions, we looked at the projected depth charts he presented on his Talking Yakyu podcast, where we was surprised to see that Hisanori Yasuda was not projected to be the starting third baseman for the Chiba Lotte Marines. We haven’t really been keeping tabs on the Marines lately, but had we been then we shouldn’t have been that surprised. After posting a 120 wRC+ over 440 PA in 2022, things have been been trending downward for Yasuda, falling to a 100 wRC+ (472 PA) in 2023, 75 wRC+ (174 PA) in 2024, and 73 wRC+ (350 PA) in 2025.
| Season | PA | AVG | OBP | SLG | wOBA | wRC+ |
|---|---|---|---|---|---|---|
| 2022 | 440 | .263 | .343 | .397 | .337 | 120 |
| 2023 | 472 | .238 | .318 | .361 | .311 | 100 |
| 2024 | 174 | .228 | .282 | .310 | .274 | 75 |
| 2025 | 350 | .243 | .303 | .290 | .273 | 73 |
Yasuda’s ability to both get on base and to cause damage have generally declined since that 2022 season, culminating in a lackluster 2025. His poor .303 OBP (25th percentile, min. 300 PA) and .243 AVG (28th pctl) make sense when you see he ran a 18.6 K% (38th pctl) and a 7.1 BB% (49th percentile). Striking out a bunch while only walking so-so isn’t exactly a recipe for success. Yasuda was generally a passive hitter, swinging only 40.6% of the time (13th pctl). While this means he doesn’t chase a lot (25.6 Chase%, 63rd pctl), it also means he doesn’t swing that much in the zone (54.3 Z-Swing%, 5th pctl), though he was probably just being selective considering he had a 90.9 Z-Con% (66th pctl). The selectivity might have lead to too many called strikes however, as even though his SwStr% was a low 8.4% (61st pctl), his CSW% was a high 32.0% (3rd pctl). That selectivity also didn’t extend outside the zone, as although he didn’t chase often, when he did he only had a 52.7 O-Con% (34th pctl) Another way to look at things is through the lens of Simple SEAGER: his Simple Selection Tendency was as high as 55.5% (87th pctl) but his Simple Hittable Pitches Taken was also as high as 40.3% (13th pctl), resulting in a sub-par Simple SEAGER of 15.2 (33rd pctl).
| Swing% | Z-Swing% | Chase% | Contact% | Z-Con% | O-Con% | SwStr% | CSW% | K% | BB% |
|---|---|---|---|---|---|---|---|---|---|
| 40.6% | 54.3% | 25.6% | 79.4% | 90.9% | 52.7% | 8.4% | 32.0% | 18.6% | 7.1% |
| Simple Hittable Pitches Taken | Simple Selection Tendency | Simple SEAGER |
|---|---|---|
| 40.3% | 55.5% | 15.2 |
It might be more interesting however to look at his power output. While not a known power hitter, Yasuda could at least squeeze out a few homers a year, though never hitting more than 9 in a season. That being said, over more than 500 PA the past two seasons, Yasuda has hit a grand total of… zero home runs. Which is, not ideal? He’s in the bottom 10th percentile in SLGcon (.354, 8th pctl) and ISOcon (.058, 8th pctl), and just barely escapes in swOBAcon (Standard wOBAcon) (.290, 11th pctl).
| SLG | ISO | SLGcon | ISOcon | swOBAcon |
|---|---|---|---|---|
| .290 | .047 | .354 | .058 | .290 |
How can we explain what’s going on here? The dominant paradigm in thinking about batted balls is through power and angle. It’s why we have exit velo and launch angle, which power xwOBAcon. Or bat speed and attack angle. Compare 2022 Aaron Judge to 2022 Eduardo Escobar: similar launch angles, very different exit velos, and consequently very different Barrel%. While NPB+ has exit velos and launch angles, they’re hard to play with plus as far as we know they don’t have data (at least publicly) for 2025 and earlier. What we do have however is batted ball distribution, which, if anything, is indicative of the latter. And he appears to have a decent distribution. If you look at his batted ball distribution, he keeps it off the ground (39.1 GB%, 71st pctl) and in the air (24.6 LD%, 91st pctl; 33.3 OFFB%, 61st pctl) while avoiding pop-ups (3.1 IFFB%, 70th pctl). All-in-all, his 60.9 AIR% (71st pctl) indicates he was hitting the ball at good angles, though the results weren’t there.
| GB% | LD% | OFFB% | IFFB% | AIR% |
|---|---|---|---|---|
| 39.1% | 24.6% | 33.2% | 3.1% | 60.9% |
In an effort to show that his batted ball distribution wasn’t abysmal, if you average the stats of the players not named Hisanori Yasuda with an AIR% between 60% and 62% (roughly Yasuda’s AIR% ±1%) weighted by PA, his SLGcon, ISOcon, and swOBAcon rise to .457 (55th pctl), .149 (62nd pctl) and .333 (49th pctl), respectively. That would put him more middle of the pack than bottom of the barrel. Alternatively, since as far as we know there isn’t any public LA SwSp% data for NPB, we can try to predict a LA SwSp% percentile from batted ball distribution using MLB data, assuming the distribuition shift isn’t severe. Okay, so briefly: we take batted ball distributions (GB%, LD%, OFFB%, IFFB%) and LA SwSp% from Savant from 2015 to 2025; fit a KNN regressor to predict LA SwSp% from batted ball distributions, performing a hyperparameter sweep for k training on 2015-2023 data and validating on 2024 data; and then take the best hyperparameter to fit the model on the entirety of 2015-2024 with a final test on 2025 data. We hope that the notorious dead ball of NPB only affects exit velos and not launch angles, and that even if there is any discrepancies in launch angle distributions, the relative ranks of players are preserved. That being said, Yasuda is in the 93rd percentile of NPB hitters in this “x LA SwSp%” (36.9% if anyone’s curious).
| AIR-xSLGcon | AIR-xISOcon | AIR-xswOBAcon | x LA SwSp% pctl |
|---|---|---|---|
| .457 | .149 | .333 | 93 |
Okay so his launch angles were presumably decent enough, perhaps good even, and assuming power (the other half of the power-angle paradigm) typical for his distribution of batted balls, he should have been performing better than he did. But we know he didn’t, so he probably wasn’t hitting the ball with that much power. Yet again, we don’t appear to have NPB+ data for 2025 so we don’t have his exit velos, but we do have quality of contact stats which can hopefully serve as a good enough proxy. Yasuda’s 24.6 Hard% is quite average at the 53rd percentile. If we repeat what we did for AIR% by performing a PA-weighted average of hitters between 24 and 26 Hard%, we get .465 SLGcon (57th pctl), .148 ISOcon (61st pctl), and .340 swOBAcon (55th), which places him a little better than average, assuming he hit those balls at angles typical of people around his Hard%.
| Soft% | Med% | Hard% | Hard-xSLGcon | Hard-xISOcon | Hard-xswOBAcon |
|---|---|---|---|---|---|
| 18.8% | 56.6% | 24.6% | .465 | .147 | .340 |
Now it seems that Yasuda hit the bat hard above average and hit the ball at good angles. Since hitting the ball well requires both, it suffices to assume that his underlying talent as jointly measured by his batted ball and contact quality distributions should be pretty decent. If we repeat our LA SwSp% experiment but regress batted ball (GB%, LD%, OFFB%, LD%) and quality of contact distributions (Soft%, Med%, Hard%) to damage metrics, we see significant improvements at .509 SLGcon (78th pctl), .183 ISOcon (78th pctl), and .361 swOBAcon (71st pctl). We should note however that if you compared these expected stats amongst themselves, the percentiles would be lower (61 pctl, 62 pctl, 61 pctl), but the idea is we generally see increases not seen when projecting damage metrics from angles and power independently (with the exception of ISOcon).
| Hard-Air-xSLGcon | Hard-Air-xISOcon | Hard-Air-xswOBAcon |
|---|---|---|
| .509 | .183 | .361 |
With at a 71st percentile expected xswOBAcon but 11th percentile swOBAcon, is it possible that Yasuda was simply that unlucky? His .301 BABIP was 46th percentile, but that’s different from being the unluckiest player in the league. One possible idea is that the joint distribution between Yasuda’s batted ball types and qualities of contact was poor. He may hit a lot of balls in the air and he may hit a lot of balls hard, but if he doesn’t hit balls hard while hitting them in the air, then they aren’t really going anywhere.
Unfortunately, we don’t seem to have publicly available pitch-level data to measure something like Hard AIR%. One of the few things we can do, which should be taken with a grain of salt as we’re essentially using results to explain process rather than the other way around, is look at Yasuda’s batting average on grounders and fly balls. In a league where the batting average on grounders (BAGB) is .241 and on fly balls (BAOFFB) is .330, Yasuda actually has reverse splits. Not only that, but they’re quite far apart too as his .282 BAGB is good for 74th percentile while is .213 BAOFFB is a mere 7th percentile. This doesn’t guarantee that his hard hit balls here mostly grounders, but it does point to the possibility.
| BAGB | BAOFFB | |
|---|---|---|
| NPB | .241 | .330 |
| Hisanori Yasuda | .282 | .213 |
Another thing to point out, and something that may help illustrate the previous point, is spray angle. Using spray data from Sanspo (as opposed to FanGraphs), Yasuda’s 37.4% Pull% is good for 57th percentile, which when paired with his AIR% (59.4%, 72nd pctl from the same data source) might make one think he pulls a lot of fly balls, which typically leads to good outcomes. However, his 14.4 Pull AIR% is only 46th percentile, meaning that even though he pulls batted balls and hits them in the air, he doesn’t do them at the same time that often.
| AIR% | Pull% | Cent% | Oppo% | Pull AIR% |
|---|---|---|---|---|
| 59.4% | 37.4% | 42.9% | 19.7% | 14.4% |
Hisanori Yasuda’s been having a rough time as of late, to say the least. He started the season on the farm if that’s any indication. He had a lower back injury in 2024
Data
Fangraphs, SPAIA, Sanspo