Let me begin by apologizing to all those that have been expecting (and have probably since given up expecting) this article for nearly 4 weeks now. Hopefully things are once again settling down and I can get back to making contributions around here.
While researching the effects of Reno on Diamondback pitching development, I discovered a few things. The first is that the amount of readily available statistical data for the minor leagues falls woefully short of providing a complete picture of how players performed. It's difficult even to pin down when precisely moves were made in terms of promotions and demotions to and from the parent club and AAA. The second thing I learned is that, despite the number of good pitching years to come out of Arizona, the Diamondbacks have developed a rather pitiful amount of home-grown pitching talent, Brandon Webb notwithstanding.
It's not as though every team in baseball has filled their rotations from talent developed within the system. But the Diamondbacks as a whole have been rather woeful at developing pitching for their staff as a whole. From 2009 through the break in 2014, here is how the Diamondbacks pitching development has fared (not counting pitchers developed by and brought up to the organization prior to 2009, thus there will be no Doug Slatens):
Starters that have made 5 or more starts for the team: 7*
Barry Enright, Wade Miley, Josh Collmenter, Tyler Skaggs, Patrick Corbin, Mike Bolsinger, Chase Anderson
If the 2014 season ended today, this group would collectively have turned in 7 seasons of pitching with an ERA+ over 100, and Collmenter accounts for 3 of them.
Relievers that have pitched 30+ innings (combined seasons): 6*
Esmerling Vasquez, Joe Paterson, Sam Demel, Bryan Shaw, Leo Rosales, Josh Collmenter
*counting Collmenter in both lists.
Over five and a half seasons, the Diamondbacks have only managed 30 or more total innings out of a total of six pitchers in their system. Of those six, one (Collmenter) is now a starter. And it gets worse. Listed here are the total number of seasons in which those pitchers produced 20+ innings for the team and their combined Diamondback ERA+.
Vasquez: 3/92
Paterson: 1/76
Demel: 2/84
Shaw: 2/128
Rosales: 2/90
Collmenter: 4/112
Excluding Collmenter from the count here (since his ERA+ was counted for the above) this group has managed only 6 "seasons" of ERA+ over 100, and that's giving them the 116 that Paterson put up over 2 innings in 2013 as a season.
Needless to say, for a team like the Diamondbacks, a mid-market team with limited resources, this level of production from the pitching pipeline is not encouraging, especially given the number of high profile arms to go through the system over the last five years.
In part 2, despite the small sample size, we will look at the 5 starters listed earlier and two other pitchers that have been part of the process but have since moved on. In it we will look at results and trends.