Hitter xwOBA Underperformers & Overperformers

We’re just over a fifth of the way through the season, which feels like prime time to start making trade offers. I typically use this time to identify my team’s overperformers and underperforming targets on my leaguemates’ teams and then send out a flurry of offers. You never know how other owners value your overperforming players or whether they have become impatient with their own underperformers. So it’s worth finding out by engaging in trade talks. Today, I’ll review the top underperformers and overperformers by comparing wOBA versus Statcast’s xwOBA. We know the latter isn’t perfect, but it’s the best metric we currently have to evaluate expected performance to-date.

Can you use a catcher upgrade? Odds are you can! Say hello to Salvador Perez who leads qualified hitters in xwOBA underperformance. While I am absolutely shocked to see an xBA of .331 that he has almost zero chance of achieving, the xSLG tells us that he has significantly underperformed in power. All his Statcast power metrics look normal and he’s even sitting with an elite 15.2% HR/FB rate. Yet somehow he’s posted just a 4.5% HR/FB rate and .138 ISO. That seems like a magic act, so you would have to imagine that at some point, and perhaps very soon, those extra-base hits and homers will start racking up.

Andrew Vaughn seemed like the perfect “he has to break out at some point after posting solid and stable skills for four straight seasons” choice this year, but instead, nothing has gone his way. Like Perez, he has somehow managed an elite 14.6% Barrel%, and a HardHit% just over 50%, but just a 7.3% HR/FB rate and .104 ISO. How is that possible?! Sure, some of that .204 BABIP is deserved thanks to a lowly 13.5% LD%, but he looks seriously due for a power surge. He could make for a good target in AL-Only leagues if you need a corner guy.

It’s not often you Yordan Alvarez sitting with a .279 wOBA, but Statcast thinks it’s all just been bad luck so far. The skills here remain strong, albeit down from his peak marks, so it’s only a matter of time before he turns things around. Of course, we’ll have to wait a bit longer now since he just hit the IL.

I was quite bullish on Brandon Lowe given the Rays new temporary home park, but failed to roster him in any of my three leagues. While he has managed to stay healthy so far, he hasn’t done much offensively. The Statcast power metrics are all right in line with his history, so it’s weird seeing him with just a .102 ISO, but it’s also weird that he has posted a perfectly reasonable 14.8% HR/FB rate. Incredibly, the four home runs he’s hit have been his only four extra-base hits all season. That’s right, he’s still searching for his first double! That’s crazy. So from a fantasy perspective, a rebound closer to his xwOBA won’t yield as much as some of the others since it’s mostly just the lack of doubles right now killing his wOBA.

Alec Bohm is 127 at-bats into the season right now and he has yet to hit a home run. That’s even with the second highest HardHit% of his career and his highest Barrel% since his double digit mark during the short 2020 season. Everything here looks completely normal, so expect him to quickly get back on track. Of course, most of his valuable is tied up in batting average and a good RBI slot in the order, which always made him risky as he just doesn’t have the power to give him a high floor.

After a poor 2024, it would be easy to wonder if Marcus Semien is experiencing an accelerated offensive decline. But Statcast suggests the decline hasn’t been as swift as it appears. Like some of the others, the HardHit% and Barrel% all look fine compared to his history, but he has managed just a 4.5% HR/FB rate and microscopic .058 ISO. There does seem to be some aging effects here, though, as his strikeout rate has spiked and his SwStk% is the highest it’s been since his small sample debut back in 2013. He has also struggled to hit line drives, hampering his BABIP.

This was not the beginning to his sophomore season Dylan Crews owners expected. But then again, it’s not significantly worse than his weak output during his cup of coffee last year. And even last year he dramatically underperformed his xwOBA. It’s way too early to consider this a trend, but something worth monitoring. The home run power has been here, though he has oddly struggled to hit doubles, knocking just one so far this season. He has also continues to post a low BABIP, even though his LD% is up from last year, but still below league average. The strikeout rate surge, combined with the drop in walk rate, is a bit concerning. Overall, the skill set doesn’t look great, but the upside here remains intriguing.

Otto Lopez has made some changes to his skill set since last year and he actually looks like a decent player. Too bad his BABIP had collapsed before he hit the IL so it’ll be a while before he’s able to try rebounding.

Holy cow, Matt Olson’s xwOBA is even higher than his career high mark in 2023 during his career year! Amazingly, both his HardHit% and Barrel% are sitting at career highs, and yet his HR/FB rate and ISO marks are at career lows. Whaaaaaaaaat?! Oh, and his walk rate has surged to an elite level, while his strikeout rate has dropped below 20% for the first time, driven by a single digit SwStk% for the first time. If I hadn’t seen his results, I would have guessed he was back to his 2023 hitting ways en route to another career season. He looks like a prime trade target.

Bryan Reynolds had been hampered by a triceps issue for half of the season so far, which limited him to DH duties through mid-April. He’s back in right field since though, but he’s still been a massive xwOBA underperformer. Like the others on the list, the Statcast metrics look great and his Barrel% is actually at a career high. But his HR/FB rate and ISO sit at career lows. Reynolds is seemingly a bit boring, but owners should avoid the temptation to sell low here.

For some reason, the gaps between wOBA and xwOBA are much smaller for the top overperformers than underperformers, so this list is shorter.

I thought that perhaps Luis Arraez was a consistent xwOBA overperformer as he just seemed like the type of guy who could be. He’s not. He’s essentially flip-flopped overperforming and underperforming each season, so his current xwOBA really stands out. Statcast ain’t buying his sudden power outburst, and looking at his metrics, I could see why. His HardHit% is at a career low, and it was always low to begin with. Oh, and he has yet to even barrel a ball, leaving him with a 0.0% Barrel%. Everything else looks normal and you’d even expect his .286 BABIP to rebound. But that home run pace isn’t going to stick, though I’m sure most owners aren’t going to care.

Andy Pages has been a hot pickup recently thanks to a surprisingly strong start to the season, delivering both power and a touch of speed. Statcast thinks it’s all been a mirage. Although his metrics look reasonable, the Statcast power metrics make both his HR/FB rate and ISO look quite flukey, while his extreme fly ball tendency make it hard to believe he could sustain a .319 BABIP. I’m betting he ends up right back in a lot of free agent pools over the next couple of weeks as owners who added the hot player of the week end up dropping said player.

Ooooof, I did not want to see Victor Scott II’s name here as he was part of several of my bold predictions after an encouraging spring training that gave me hope he had transformed into a new player. Amazingly, Statcast isn’t buying his current level of power, even though his HR/FB rate sits at just 6.9% and ISO at .133. But the biggest red flag is the .373 BABIP, though a huge LD% and zero pop-ups have certainly helped keep that BABIP afloat. It’s pretty clear that he’s an improved player versus last year, but I probably put too much stock into his improved strikeout rate and power output during spring training. I’m still waiting for his .356 OBP to get moved toward the top of the order, but if it hasn’t happened yet, it may never, which hurts all his counting stats.

The Rockies are finally doing something right by letting Hunter Goodman play every day and his xwOBA overperformance has kept him in the lineup. Sadly, if he does slump toward that xwOBA, he might find himself back in Triple-A, because, ya know, the Rockies. His .325 BABIP is clearly the source of the overperformance, and it’s surprising he’s recorded such a mark given the low 14.1% LD% and extreme fly ball tendency. Sure, Coors does help here, but not to this degree. I would also expect an increased strikeout rate moving forward given his high 16.2% SwStk%. Overall, expect the continued power, but a decline in batting average, perhaps a precipitous one, and any extended slump could get him benched, or worse, demoted to the minors.

Heyyyyy, there’s our good friend Jose Altuve, the poster boy for xwOBA overperformance! He has overperformed over the last four seasons and then if we skip when he marginally underperformed during the short 2020 season, we have five straight seasons of overperformance again, bringing us back to the first season we have xwOBA calculated. What does he do that xwOBA fails to capture?! That said, his .259 xwOBA is far and away the worst mark of his career. The good news is that he has routinely overperformed by at least the amount he is currently doing so, so there’s no expectation he’ll slide further to meet his xwOBA. Still, it’s not promising for the 35-year-old, as he might be en route to his worst offensive season since 2013.

So Alex Bregman is simply loving his new Fenway Park home, eh? Nope, he has actually posted a higher wOBA on the road! This is mostly a batting average thing as Statcast does not think he’s deserving of a .350 BABIP. Amazingly, that would be just the second time his BABIP exceeded even .290 over a full season. His power increase looks mostly legit so far, though, as he is sitting with the highest HardHit% and Barrel% marks, by far, of his career.