Hitter xwOBA Overperformers — June 30, 2021, A Review

Alas, it’s the final in-season metric review of the year! It took a while, but I think it’s important to perform these reviews to be held accountable for what I share. It’s not enough to just share analysis, my opinions, and advice if it’s all wrong! So these reviews have helped prove that the in-metric analyses were worthwhile, as the majority of players moved in the direction expected. Today, we finish up by reviewing the xwOBA overperformers through June 28. Let’s find out how they performed over the rest of the season.

Success again! Six of the seven non-injured (Nick Madrigal’s last plate appearance came on Jun 9, due to injury) players suffered a decline in wOBA over the rest of the season. The group’s unweighted average xwOBA over the rest of the season ended up pretty darn close to its xwOBA over the first half. As a reminder, xwOBA was not formulated to be predictive. It’s strictly a backwards looking “how should the player performed?” type metric. That doesn’t mean it can’t be used for predictive purposes, of course, as Alex Chamberlain did the math a couple of years ago and 1st half xwOBA correlated with 2nd half wOBA better than wOBA itself.

Joey Wendle was quite solid in the first half, but xwOBA didn’t believe it at all. Sure enough, he fell flat over the rest of the season, posting a sub-.300 wOBA, similar to his xwOBA from the first half. Both his ISO and BABIP fell over the rest of the way, and he ended up finishing with a wOBA below his 2020 mark.

We’re always looking for a non-elite catcher that won’t kill us, and Tucker Barnhart fit the bill early on. But Statcast warned us it wasn’t real, and he faded bad over the second half. Here, it was due mostly to his BABIP collapse, which was clearly unsustainable early on. His ISO declined as well, resulting in his lowest mark since 2015, while his HR/FB rate was also his lowest since the same year.

Jared Walsh was quite good early on, convincing his owners that his tiny sample 2020 was no fluke. While he remained decent enough, it was still a big fall from his early performance, as both his BABIP and ISO predictably fell. He was also unable to maintain his massive strikeout rate gain in 2020, though a 26% mark is perfectly acceptable for a guy with his power. Now, the one remaining issue is his FB%, which fell just under 30%, a rate far too low for someone with mid-20% HR/FB rate power. Depending on how high he could push that up, 40 homers could be within reach.

Cedric Mullins was one of the year’s biggest fantasy surprises and profit makers for his owners. He was the best performer in the first half on this list, but even xwOBA suggested he was deserving of a mark far better than any of the preseason projections expected. So while he surely had been the beneficiary of good fortune, he clearly had taken an unanticipated leap forward. While he declined over the rest of the season, due to a drop in BABIP (his ISO actually rose slightly), he was still plenty good. It’s hard to imagine he won’t be overvalued next season, but it’ll really depend on your leaguemates’ expectations.

Trent Grisham completely bombed in the second half, posting a sub-.300 wOBA, as both his ISO and BABIP took a nosedive. Maybe it was injury related or maybe this is actually his true talent, which is close to his 2019 small sample, rather than his 2020 small sample. He still owns power and speed, so I’d be fine buying here at a discounted rate, depending on how secure his playing time appears.

There’s Randy Arozarena again defying the xMetrics! He was the only one on the list whose wOBA didn’t decline over the rest of the season. Not only did he avoid a decline, he actually increased his wOBA meaningfully, as he boosted both his ISO and BABIP over the rest of the season. I really don’t know what to make of him, which likely means he’ll end up on someone else’s fantasy team.

Yuli Gurriel enjoyed the second best first half performance on this list, but his power disappeared in the second half, bringing down his wOBA. It was still a nice rebound off his disappointing 2020, though it was driven entirely by a bounceback in his BABIP, which spiked to a career best. Since he’s essentially just a batting average guy whose runs scored and RBI totals benefit from hitting in the middle of the order, I think he could quickly drop to replacement level, so I’m not really interested here at age 37.