2019 HR/FB Rate Decliners — A Review

In mid-February, I compared the xHR/FB rate my equation spit out to the batter’s actual mark in 2018 to share a list of six batters the formula would suggest possessed significant HR/FB rate downside in 2019. The record home run rate this year is going to probably make the picks look bad, but let’s take a gander at the names and the results anyway to find out if that was indeed the case.

Overall, this was a solid showing, especially considering the league average record high HR/FB rate. Of the six batters, only half suffered HR/FB rate declines, but those declines were significant. Of the other half that saw increases, two of the three enjoyed jumps that were actually a lesser degree than the league. Really, only Eugenio Suarez laughed at the notion he would suffer a precipitous decline in HR/FB rate.

Luke Voit was one of 2018’s small sample power surgers. In just 143 at-bats, he bashed 15 homers, driven by an absurd 40.5% HR/FB rate. It was plainly obvious that he, nor anyone else, possessed such an extraordinary true talent level. So we really didn’t need any sort of equation to predict regression. However, that he kept his mark above 20%, which was well above any mark he had posted in the minors, validates that his 2018 power show was kinda for real. Not to the same level, but Voit certainly took his power up another notch.

Ryan O’Hearn enjoyed a similar surprise power spike over a small sample last year, though not nearly to the same degree as Voit. He was coming off a paltry 9.6% HR/FB rate at Triple-A, so it was hard to believe a 25% mark in the Majors was sustainable. Sure enough, his HR/FB rate plummeted during his second time through the league. This looks more like his true talent HR/FB rate. Given that he’s a lefty with weak BABIP potential, he’s probably not an every day guy in the future.

When a catcher who has posted a HR/FB rate barely above 3% suddenly pushes that into the mid-teens, the knee-jerk reaction is to call it a fluke. Since xHR/FB rate also agreed, it seemed obvious that Omar Narvaez would be a bust this season. That didn’t happen, as Narvaez boosted his HR/FB rate even higher, though he failed to keep up with the jump in leaguewide HR/FB rate. Since he also transformed himself into a fly ball hitter, he managed to more than double his home run output. That’s going to be the key as to whether he could knock another 20 dingers in 2020.

The top tier of power hitters typically outperform xHR/FB rate because most formulas struggle at the extremes. So although Franmil Reyes appears here, it would have been silly to assume major regression, given that his Statcast metrics were all elite. Reyes ended up posting a 33.8% HR/FB rate with the Padres, but regression eventually reared its ugly head, as that mark declined to a more reasonable level at 25.6% after joining the Indians. I’d still like to see what would happen if he pushed that fly ball rate into the high 30% range or above 40%.

Yes, David Peralta did miss time to injury, which could perhaps explain the decline in HR/FB rate. But the fact that it fell right back to his pre-2018 marks suggests that it was really just 2018 as the outlier. He also hits a ton of grounders, which is odd coming from a guy with power and not a whole lot of speed. It has helped his BABIP, but caps his home run potential, unless he could push that HR/FB rate mark back into the 20% range.

Eugenio Suarez is the formula’s biggest miss here, as Suarez has now increased his HR/FB rate every single season in the league. That’s pretty amazing. Surely the Tigers didn’t see this coming! Suarez seemed to have clearly changed his approach this year to optimize his home run power thouh. His strikeout rate spiked to a career worst, backed by a career high SwStk%, while his FB% jumped above 40% for the first time since his 2014 debut. That’s the kind of results you get when you decide to really swing for the fences. It most certainly worked, as his wOBA rose marginally to a new career high, though it was barely above his 2018 mark.