Diamondbacks Minor League Parks a Pitcher's Gauntlet

The organizations parks and leagues combine to create the 2nd most hitter friendly environments in all of minor league baseball

© David Calvert - Calvert Photography

Each year Matt Eddy of Baseball America compiles park factors for all 120 minor league ballparks at four different levels, Low A, High A, AA, and AAA. This data helps us better understand the run, homer, and overall hit environments of the parks the teams play in. That understanding is critical to putting statistics in context when trying to evaluate prospects. The differences from league to league and park to park can be extreme. 

Eddy rates each league, and the runs, homers, and BABIP (batting average on balls in play) component to each park.  100 equals league average within that league. Over 100 favors hitters relative to that league and under 100 favors pitchers. A number of 110 means the park inflates that offensive measure by 10%. He then puts that number into  context against the overall league run environment to create a rating he calls TRC, where the higher the number the more hitter friendly. The highest run environment of all 120 ballparks was 6.91, (Amarillo) and the lowest was 4.35. (Palm Beach)

You can read more about Eddy's methodology and see all the data tables at that link in the highlighted text in the first paragraph. What follows is a summary of just the D-backs affiliated parks. 

Greater Nevada Field, Reno Aces, PCL AAA, 6.13 TRC, 93rd percentile

It's probably well known to many Diamondback fans that their AAA Reno affiliate in the Pacific Coast League plays in a hitters park in a hitters league. For years we have seen players put up gaudy numbers for the Aces only to struggle to come close to those numbers in the majors. Beyond the obvious difficulty in making the jump from AAA to MLB, the environment there often inflates hitting numbers to a large degree. That can cause us to sometimes have unrealistic expectations of a hitter, or conversely be pleasantly surprised by a pitcher coming up to MLB with an inflated AAA ERA. 

Surprisingly perhaps, Greater Nevada Field, which sits at 4500 feet elevation,  only ranks as the 5th most hitter friendly park within the PCL.  Albuquerque, El Paso, Las Vegas and Salt Lake rank even more extreme. The home run park factor is just 87, or 13% below the league average. The thing is the PCL is still the most homer friendly league in all of the minor league, roughly 25% higher than average. So 13%  less than the PCL average is still more than the entire affiliated minor league average.  

That's why you see pitchers like Drey Jameson (6.95 ERA in AAA) or Ryne Nelson ( 5.43 ERA in AAA) surprise us in MLB. At the same time, this why you might see a player such as Cooper Hummel, (.950 OPS in AAA) or Alek Thomas, (.936 OPS in AAA) put up an OPS 300 points lower in MLB.

Hodgetown, Amarillo Sod Poodles, Texas League AA, 6.90 TRC, 100th Percentile

It may come as a surprise for some to learn that the D-backs AA affiliate, the Amarillo Sod Poodles of the Texas League, play in the most hitter friendly environment in all of affiliated minor league baseball. The Texas league is already a hitters league, behind only the California League and the PCL in average runs per game. And within this hitter friendly league, Hodgetown, which sits at 3,600 ft. elevation is off the charts, with a 142 Runs park factor and a whopping 165 home run factor. That means 42% more runs are scored and 65% more homers are hit in that ballpark compared to he rest of the Texas League

Looking at pitching home/road splits for some key Diamondbacks pitchers who threw most of their games in AA this year is illuminating:

Slade Cecconi  5.74 home, 3.27 Away

Blake Walston 5.43 home, 4.02 Away

Brandon Pfaadt 4.54 home, 3.29 Away

Of course the opposite is true for most hitters who called Hodgetown home for any length of time this year saw home/road OPS splits between 75 to 250 points. 

Here is a video interview with Pfaadt, who won Diamondbacks pitcher of the year award by staying aggressive, regardless off the ballpark environment.

Ron Tonkin Field, Hillsboro Hops, North West League A+ 4.59 TRC, 8 Percentile

The Hillsboro Hops of the advanced class A+ Northwest league is the only Diamondbacks minor league affiliate that plays in a pitcher's league, and they play their home games in a pitcher's park that suppresses home runs. The park run factor is is 87, 13% below average, and the homerun factor is just 53, meaning the park reduced homers by nearly 50%.

A.J. Vukovich had a .842 OPS on the road vs. just a .675 OPS at home. Caleb Roberts had a .900 OPS on the road and only .593 at home. These are a couple of prospects who could surprise by putting up big numbers in Amarillo next year. 

On the flip side, several pitchers that pitched a lot of innings for the Hops had much lower ERA at home than on the road. For example Luke Albright had a 3.92 ERA at home but 7.35 on the road in 123 innings. Scott Randall had a 2.31 home ERA vs. a 5.35 road ERA. Perhaps encouragingly, Jameson Hill had a reverse split, 5.37 at home, but 3.88 on the road. 

Valley Strong Park, Visalia Rawhide, California League, Class A, 5.83 TRC, 88 Percentile

With a league average of 6.07 runs per game, the California league has the highest scoring average of any league in the minors. So despite being the second most pitcher friendly park in that league, Valley Strong Park still ranks as a hitters environment, as can be seen by the 5.83 TRC which is in the 88th percentile. 

With many small ballparks, poor quality infields, and a number of dry California desert environments with high winds, the pitcher's era and batters OPS will always be inflated in this league.

Summary

With three out of the four Diamondbacks minor league parks being in extreme hitters environments, the organization ranks 2nd among all MLB organizations in terms of hitter friendly environments overall. Only Oakland has a tougher environment for pitchers. 

Earlier in July we spoke pitching coach Brent Strom who gave some insights into how the team evaluates pitchers in such environments

“We monitor a great deal. One of the ones that is a big one for me is the ability to throw something other than your fastball when you’re behind in the count. Something off speed. These major league hitters hunt, they’re like sharks smelling blood in the water. When they sense that a young guy cannot throw something off speed over the plate. they really start to hunt the fastball, and then they start to hunt it in certain locations. We monitor guys that can throw a 2-1 change or a slider, something over the plate.

The ERA’s in Reno or Amarillo, they’re not important to me. What’s important to me is those peripheral type things, like pitching ahead in the count, what can you throw when you’re behind in the count. What can you go to 3-2. Do you always default back to the fastball for fear of walking somebody.”

“What you find out when you have pitchers that pitch in Reno and Amarillo you find out who can withstand. I think we’re seeing with our young pitchers up there now, when they give up a homerun for example, do they come back into the strike zone or do they start to dance away from the strike zone. Do you get a walk immediately following the homerun, or do you get strike one again.”

He also gave some fascinating info on how the higher altitude environments impact the statcast readings even on things like the “carry” or hop you get on a fastball.

“You realize when you look at 12 inches of carry in Reno, might play at 17 inches here in the desert”

Ultimately Strom summarized as such:

“What doesn’t kill me is going to make me stronger.”