When we talk about how much power a hitter has we usually look directly at home runs or extra-base hits. That’s a good place to start when looking at how much power potential a guy has as well. One thing that we can check out with Major Leaguers that we don’t have easy access to for minor leaguers is HR/FB%. You can find that stat at Fangraphs for big leaguers, but as far as I’ve been able to find, unless you build your own play-by-play database, you can’t get it for minor leaguers. Fortunately, I’ve built my own minor league play-by-play database and can run the numbers for things like HR/FB%.

Fangraphs glossary has this chart to explain the various levels of talent when it comes to HR/FB%, though it goes back to 2002, which was still in the PED era, so you may want to adjust the numbers down a percent or so for the current environment.



Excellent 20.0%
Great 15.0%
Above Average 12.5%
Average 9.5%
Below Average 7.5%
Poor 5.0%
Awful 1.0%

We also need to note that some parks are much more friendly for fly balls than others. For the Reds that would include Billings, Bakersfield and left field in Pensacola. Right field in Pensacola is at the opposite end of the spectrum and punishes fly balls in a big way.

I took a look at the Top 20 guys by home run totals from the 2014 season that are still in the system moving forward. That actually led to a list of 21 players since two players tied for 20th. I’ve sorted the list among those players by HR/FB% and left in the teams they played for to give the numbers a tad more context for their park factors.

Name Age Team HR/FB%
Juan Duran 22 PEN 26.6%
Aristides Aquino 20 BIL 26.2%
Taylor Sparks 21 BIL 22.7%
Donald Lutz* 25 LOU,PEN 18.8%
Argenis Aldazoro* 21 BIL 18.0%
Marquez Smith 29 BAK,PEN 16.5%
Jesse Winker* 20 BAK,PEN 16.0%
Sean Buckley 24 BAK,DAY 14.3%
Alex Blandino 21 DAY,BIL 12.7%
Seth Mejias-Brean 23 BAK,PEN 12.3%
Jeff Gelalich* 23 BAK,DAY 12.2%
Yorman Rodriguez 21 PEN 12.0%
Joe Hudson 23 DAY,BAK 11.3%
Kyle Waldrop* 22 BAK,PEN 9.7%
Tanner Rahier 20 DAY 9.4%
Juan Perez* 22 BAK 9.0%
Felix Perez* 29 LOU 8.6%
Sebastian Elizalde* 22 BAK,DAY 8.4%
Ryan Wright 24 BAK,PEN 7.5%
Beau Amaral* 23 BAK,DAY,PEN 5.7%
Phillip Ervin 21 DAY 5.4%

It’s not a surprise to see Juan Duran at the top of the list. He’s got the best rated power in the system and he played in a ballpark that strongly favors power to left field, where as a right hander who pulls the ball he gets a boost. The next two guys on the list both also have big power potential and also played in friendly confines.

Donald Lutz showing up next is a bit of a surprise. Lutz has plenty of power, but he also was a left hander who spent time in Pensacola where right field is very unforgiving (the ballpark yielded 12 home runs to right field, from both teams playing in the 70 home games in 2014. There were even less in 2013.) before moving up to Louisville. I did not include his big league team here.

The biggest surprise on the list for me was seeing Phillip Ervin on the bottom of the list. Ervin has power in his bat and while Dayton isn’t a place that really hurts power, it isn’t a place that helps it either. While there were obviously players lower than him that weren’t included in the Top 21 home run hitters and he was last among the hitters on the list in homers, he just stands out as a guy I would have expected to see a little higher.

It will be interesting to see how things hold up in 2015 for the guys going from hitter friendly environments to less favorable places to his, particularly those coming from Billings and moving up to either Dayton or Daytona depending on their assignment. Aristides Aquino and Taylor Sparks both are noted for their power, so the transition, at least from a power department, may not be as big for them as some others making the same move up, but a decline in overall power wouldn’t be a surprise.