2022 Review: Hitter xwOBA Overperformers by Mike Podhorzer January 25, 2023 Yesterday, I identified and discussed the qualified hitters who most underperformed their Statcast xwOBA marks. Today, let’s review the overperformers. Before sharing the list, I wanted to preemptively answer any concerns about xwOBA’s predictive value versus actual wOBA. Is xwOBA actually better at predicting future wOBA than wOBA itself is? A quick Google search yields an older FanGraphs article that calculates the in-season (1H to 2H) predictiveness of wOBA and xwOBA. Granted, that’s not exactly the same as season-to-season predictiveness, but I imagine the correlations would be similar. The article shows that 1H xwOBA predicts 2H wOBA better than 1H wOBA, though neither do a very good job. What’s also important to note is that I believe xwOBA has been improved upon since, especially by accounting for speed better when calculating xBA. That said, xwOBA isn’t perfect. It would be impossible to create a metric that is perfect for every player. There will always be some outliers on each side of the curve. That’s why I always review the player’s historical wOBA-xwOBA differentials to see if there’s a pattern. Now let’s get to the overperformers. xwOBA Overperformers Name wOBA xwOBA Diff Paul Goldschmidt 0.419 0.367 0.052 Manny Machado 0.382 0.338 0.044 Jose Altuve 0.397 0.354 0.043 Jose Ramirez 0.363 0.320 0.043 Nolan Arenado 0.381 0.339 0.042 Jeff McNeil 0.365 0.323 0.042 Xander Bogaerts 0.363 0.323 0.040 The 34-year-old veteran Paul Goldschmidt was far and away the biggest xwOBA overperformer this past season. He does not have a history of consistent overperformance, as he had actually underperformed in each of his last two full seasons, in addition to the short 2020 season. It’s pretty clear where the overperformance came from — BABIP. He posted a .368 mark, tied for second highest of his career, despite the second lowest LD% and highest FB% of his career. He also seemingly overperformed in power as well, posting a SLG significantly higher than his xSLG. Again, he has no history of consistent outperformance here and the Cardinals’ home park suppresses all extra-base hit types. He might be seriously overvalued in drafts this year. Manny Machado’s xwOBA outperformance mostly came earlier in the season, but he never collapsed to the point that his actual wOBA had a chance to catch up to his weaker xwOBA. Like Goldschmidt, Machado also hasn’t been a consistent xwOBA overperformer, so we could probably rule out that he’s doing something not captured by the generic equation. A career high BABIP, despite a very similar batted ball distribution to previous seasons, plus the second highest IFFB% of his career, is one source of the overperformance. In addition, he overperformed on the power side, as his maxEV fell to a career low (well, the lowest since tracking, which is 2015), while his Barrel% returned to single digits after sitting in double digits in three of the last four seasons. I don’t think the downside is nearly as great as for Goldschmidt, given the difference in age, but I would expect some regression this year. Unlike the above two, Jose Altuve has been a consistent xwOBA overperformer, and his underlying metrics had confounded projection systems in the past. Since tracking and excluding the short 2020 season, Altuve has overperformed his xwOBA during all seven seasons! But this year, he posted the largest discrepancy between his SLG and xSLG, as he posted the second highest HR/FB rate and ISO of his career. It’s pretty incredible the power he’s displayed, given that he has never posted a double digit Barrel%, or even one above 7.8%, and his maxEV has never even reached 110 MPH. So with some hidden power downside, are you going to bet on the soon-to-be 33-year-old also maintaining a high teen stolen base total? I think there are too many question marks here that he’s likely to be overvalued. You wouldn’t have realized it based on his fantasy stats and actual results, but Jose Ramirez actually posted the lowest xwOBA of his career since a partial 2015 season. He has overperformed his xSLG every single season of his career, so Statcast is definitely wondering how he has managed to post such impressive power numbers. However, he overperformed his 2022 xSLG by the largest margin in his career, while also overperformed his xBA by the widest margin over a full season, but most, if not all, of that is likely driven by his xSLG overperformance. There are two surprising things here — that he overperformed his xSLG even with just a 10.9% HR/FB rate, which is the lowest he’s posted since 2016, and then he still managed to post a strong .235 ISO despite the weaker HR/FB rate. A whopping 44 doubles, ranking second in baseball, helped boost that ISO, along with five triples. It would seem that given the lowly HR/FB rat, xSLG took more issue with his doubles rate, but luckily, that won’t have as much of an effect on his fantasy production, though it could shave a couple of RBI and runs scored off his totals if those doubles turn into outs. Who saw Nolan Arenado improving his performance during his second year with the Cardinals to match his Coors Field days?! Busch Stadium is one of the more pitcher friendly parks in baseball, so the major decline in results we saw in 2021 after Arenado left Coors was essentially what we expected. This year, his HR/FB rate actually fell from his down Cardinals debut in 2021, but ISO remained stable. This big driver here was a BABIP that rebounded, even though he posted both the highest FB% and IFFB% of his career. That resulted in the second most pop-ups in baseball at 41. However, xwOBA also wasn’t buying the power, as he significantly overperformed his xSLG. The challenge here is determining whether Arenado is a consistent xwOBA overperformer. Because he has called home one of the league’s most hitter friendly parks and played all but two seasons there, he overperformed his xwOBA every single season. But that’s to be expected in a major hitter’s park. His overperformance has continued at Busch, but the sample size is small at only two seasons. I’d be cautious here, but I guess until he proves he’s no longer an overperformer, assume he’ll continue to be one. Outside of a down 2021 and a rare xwOBA underperformance, Jeff McNeil has overperformed every other year. It’s an issue for fantasy owners given that he’s only shown any semblance of power once, back in 2019. Since he also barely steals bases, he has to be counted on to continue to overperform his xwOBA to maintain a strong average, otherwise he can very quickly fall into the dreaded 0-category contributor category. Players like him, whose fantasy value is primarily derived from batting average, with some bonus homers and steals here and there, are typically undervalued compared to a dollar value calculation. But admittedly, it’s hard to own them because without the big counting stats, it doesn’t feel like they are contributing much to your team. McNeil makes for a more comfortable deep league asset when you’re comparing him to poor batting averages and partial playing time, but the downside here makes me want nothing to do with him in a shallower league. I’m fading Xander Bogaerts this year. As he begins the next phase of his career in San Diego, he moves to a far less favorable hitting environment. He has overperformed his xwOBA every single season of his career. A quick look at his career home/away splits tells the story. He has posted a .357 BABIP at home, but just a .314 mark on the road. He has posted a 13.5% HR/FB rate at home, but a 9.9% mark away. It has all combined for a .373 wOBA at home and .327 mark away. Those are massive splits. As compared here, Bogaerts moves to a park that suppresses all hit types, while Fenway boosted all non-home run hit types, and was less pitcher friendly for home runs. So the park switch is likely going to narrow the gap between his wOBA and xwOBA and there’s a good chance this is the first year he fails to overperform. Of course, he was a bit of a disappointment in fantasy leagues last season, so there might be some natural rebounding going on that makes it seem like the park switch didn’t hurt him. But there’s a reason all the projection systems forecast a significant drop in batting average and a home run total that still falls below most of his previous full seasons.