Potential HR/FB Rate Surgers – 4/29/19 — A Review

At the end of April, I calculated hitter xHR/FB rate using my equation to determine who had most underperformed at the time. I identified and discussed 11 of those hitters. Let’s see how many of these hitters actually did improve their HR/FB rates over the rest of the season and how close they came to their xHR/FB marks. Remember that xHR/FB isn’t meant to be predictive, but descriptive. The difference being that xHR/FB rate helps us determine what should have happened, rather than what will happen in the future. It attempts to strip out luck, like the majority of our expected/deserved metrics.

Potential HR/FB Rate Surgers
Player xHR/FB Through Apr 27 HR/FB Through Apr 27 HR/FB RoS Diff
Jose Abreu 30.9% 17.2% 21.9% 4.7%
Freddie Freeman 28.9% 16.0% 25.0% 9.0%
Adalberto Mondesi 21.2% 9.7% 9.1% -0.6%
Avisail Garcia 28.4% 17.4% 17.2% -0.2%
Josh Donaldson 30.9% 20.0% 26.6% 6.6%
Miguel Cabrera 15.3% 4.5% 10.8% 6.3%
Ian Desmond 15.5% 4.8% 24.4% 19.6%
Byron Buxton 10.4% 0.0% 14.1% 14.1%
Justin Turner 9.9% 0.0% 20.1% 20.1%
Nicholas Castellanos 17.0% 7.1% 15.6% 8.5%
Jeimer Candelario 9.8% 0.0% 11.8% 11.8%
Unweighted Group Avg 19.8% 8.8% 17.9% 9.1%

Of 11 hitters in this group, all but two of them enjoyed increases in HR/FB rate over the rest of the season. Not only did they improve, but they did so by a significant degree. As a group, they increased their HR/FB rates by a whopping 9.1% (not weighted by number of fly balls), and even though xHR/FB rate isn’t meant to be predictive, they actually got their actual HR/FB rates pretty darn close.

As I mentioned in my initial writeup, it would have been silly to expect Jose Abreu to suddenly become a 30% HR/FB rate guy (though 2019 certainly fueled such a transformation for many others). So his appearance on the list is a good illustration of the caveat I shared in the intro — just because the xHR/FB metric suggests Abreu “deserved” a significantly higher HR/FB rate doesn’t mean it’s going to jump to that level over the rest of the season. Sure enough, it did rise, and even jumped above 20% for the first time since his rookie campaign, but still came nowhere close to that first month xHR/FB mark.

It was only a matter of time before Freddie Freeman would finally get his HR/FB rate above 20%. His skills continue to be worth salivating over, as he combines excellent plate discipline with tons of line drives and few pop-ups.

Adalberto Mondesi was one of just two on the list that suffered a HR/FB rate decline over the rest of the season, despite having posted an xHR/FB rate over 20% in the first month. His HR/FB rate was actually more than cut in half from his fantasy breakout half season in 2018. Next year he’ll be returning from shoulder surgery, so it’s anyone’s guess as to how that might affect his power output.

Avisail Garcia is the other member of the list who failed to improve his HR/FB rate the rest of the way. Though, his rest of season HR/FB rate was just barely below his first month mark. He remains a solid contributor when he starts, but with the Rays love of shuffling players in and out, it’s a frustrating experience owning him in weekly transaction leagues.

Josh Donaldson did exactly what xHR/FB rate figured he would do. After an injury-shortened 2018, Donaldson rebounded strongly, actually posting a career best HR/FB rate, while his skills remained excellent.

Sure, Miguel Cabrera improved over the rest of the season, but it was hard not to given his measly first month HR/FB rate. And his improvement still resulted in a meager mark. In the end, he posted a single digit HR/FB rate for the first time in his career. Is this truly the end of one of our generation’s best hitters or does he have one last hurrah in his bat? Sadly, heading into his age 37 season and with lingering injury issues always cropping up, I’d bet on the former.

I was right to remain optimistic about Ian Desmond and to stubbornly hold onto him after a weak first month, but even owners who stuck with him didn’t get a whole lot for their faith. He lost playing time to a host of other outfielders and his nine straight seasons of double digit steals streak has officially come to an end. He swiped just three bases, which combined with his sub-500 plate appearance total, resulted in a worthless shallow mixed league player.

Shocker, Byron Buxton failed to play a whole season again due to injury. But, he fully rebounded after the first month and his end of season HR/FB rate almost matched his first month xHR/FB rate. He continues to tease us with his exciting power/speed skills, but health now has become the biggest question mark.

From April zero to rest of season hero, Justin Turner surely made us question whether his time has run out after such a slow start. But his xHR/FB rate was right in line with his previous two seasons, and he ended up exploding the rest of the way en route to a career best HR/FB rate. His skills remain pretty strong, but he’s getting up there in age.

Ahhh, it’s Nicholas Castellanos, the perpetual xHR/FB rate underperformer. But all he really needed to do is get out of Detroit! His HR/FB rate with the Tigers sat at just 9.2% before he was shipped to the Cubs, where he burst out for a 23.2% HR/FB rate. His skills are superb and he should be hitting 30 bombs a year with a strong average.

Jeimer Candelario’s poor opening month got him demoted to the minors. He eventually returned and rewarded the Tigers for keeping the faith. That said, even though he improved, he still needs to show more power or a full-time job will be difficult to hold onto.

We hoped you liked reading Potential HR/FB Rate Surgers – 4/29/19 — A Review by Mike Podhorzer!

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Mike Podhorzer is the 2015 Fantasy Sports Writers Association Baseball Writer of the Year. He produces player projections using his own forecasting system and is the author of the eBook Projecting X 2.0: How to Forecast Baseball Player Performance, which teaches you how to project players yourself. His projections helped him win the inaugural 2013 Tout Wars mixed draft league. Follow Mike on Twitter @MikePodhorzer and contact him via email.

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