ESPN Home Run Tracker Analysis: The Downsiders

Two years ago, I conducted an exhaustive study of ESPN Home Run Tracker data. At that time, it was the primary tool I used to validate a batter’s power, before we got into the sexy new batted ball distance, and then combined that with SDD and angle. The short story is I found that hitters with an unusually high percentage of “Just Enough” (JE) homers saw their HR/FB rates decline the following year, significantly more than the rest of the player population. On the other hand, those who hit a high percentage of “No Doubt” (ND) homers maintained their HR/FB rate much better than the rest of the group.

What’s interesting is that now we have two sources of HR/FB rate validation — this analysis and my xHR/FB rate. The hope is that they agree on the names, but I don’t know yet. So I will be cross-referencing the names I list here and discussing any disagreements.

Today I’ll begin by taking a look at the hitters whose high JE% suggests some downside. I only included players who hit at least 15 homers. The average JE% was 32% for the group.

Yoenis Cespedes — 59% JE%

Shocking (not sarcasm). Cespedes managed just a 9.6% HR/FB rate, well below his previous marks between 14% and 15% and now we learn that even those homers were essentially wall-scrapers. Sure enough, his batted ball distance fell precipitously by 15 feet, while his SDD also dropped to a career low. My xHR/FB rate formula spit out 13.2% suggesting that he was still a bit unlucky, but that was a far cry from his previous marks of around 17%. He has now been around 3% less than his xHR/FB rate in his first three seasons, which may suggest that he’s doing something not captured by my formula.

Or, his home park has hampered his output given its 96 RHH home run park factor. When checking his splits though, that no longer seems like the explanation as he has posted a higher home mark than away. Whatever the explanation here, he’s a question mark next year, as only a career high in both plate appearances and fly ball rate kept his home run total above 20.

Yan Gomes — 57%

Gomes enjoyed an excellent fantasy performance and his HR/FB was seemingly in line with his small sample history. His xHR/FB rate also sat at almost exactly his actual mark and his distance and angle were both strong. The high JE% should certainly give one pause, but nothing else screams fluke. I’d project only very minor regression just given his limited Major League history.

Anthony Rendon — 57%

I was notoriously bearish on Rendon heading into the season, owing to both his lineup position and not enough pop to offset the apparent lack of speed. His 10.4% HR/FB looks quite reasonable and his 13.3% xHR/FB rate driven by a nearly eight foot jump in distance even suggests further upside. But 57% JE homers puts a damper on things. I had personally believed the power was legit, but now I’m a little less certain. And since he you have to assume a dropoff in stolen bases, he’s a huge risk in the second round, where I keep seeing him getting drafted. He’s not going to combine for anywhere close to 194 R+RBI again, so I just don’t see him earning his cost.

Mike Napoli — 53%

Napoli’s batted ball distance was over 300 feet and his xHR/FB rate was right in line with his actual mark, which itself was at its lowest since 2009. Once again the Home Run Tracker numbers are arguing with the other data. His SDD hit a career low, so perhaps that matches with the high JE%. He missed time last year due to various maladies, including a finger and back injury. One might assume that affected his power, but then I must ask why his distance wasn’t down. Obviously, without big-time power, Napoli isn’t much of an asset in fantasy leagues and at age 33, he might not be much more than replacement level in a shallow 12-teamer.

Justin Morneau — 53%

Not surprisingly, Morneau enjoyed a renaissance in his first year with the Rockies, but that was mostly due to an inflated BABIP and a significant cut down on strikeouts. His HR/FB rate was right in line with his previous two seasons. And once again, xHR/FB rate has a different take, thinking that his combination of distance, angle and SDD should have produced a nearly 15% HR/FB rate, versus the 11.5% mark he actually posted. Before looking at this data, I had figured a bit more power this coming year, but a sub-.300 batting average. So now I’m throwing up my hands.

Adam LaRoche — 50%

LaRoche posted his second highest HR/FB rate since 2006, but his xHR/FB rate metrics have been rather consistent since 2012, suggesting the low HR/FB rate in 2013 was the fluke. His JE% suggests downside, but his xHR/FB rate says he posted exactly what he deserved to. Of course, the more important matter is his move from Nationals Park to The Cell. The former sported a LHH HR factor of just 95, while The Cell augmented lefty home runs by 6% for a 106 factor. That’s a nice swing and should offset some of the possible regression he experiences due to aging.

So this didn’t exactly go as planned. Every hitter above had an xHR/FB rate around or above their actual marks, which is totally opposite of what their high JE% suggests. Which data point, the JE% or xHR/FB rate, do you agree with for these hitters?