Who’s hot in the Diamondbacks farm system?

With an off-day today, I figured we might take a look at the numbers put up by prospects in the Arizona farm system so far this year, and see who’s standing out. Note: this is based entirely on the stats. As we all know, these can be affected by luck - a player can see his numbers boosted (or depressed) by balls dropping in, especially over a smaller sample size. There are also wide differences in environments across the farm system. The most obvious example is the dreaded “Reno effect,” which causes every hitter with the Aces to look like a the second coming of Ted Williams. As a guide, here’s a summary of the numbers put up at the plate by each of our affiliates.

You can see the Reno Aces have been averaging one and a half runs per game more than anyone else, which causes me to all but discard any hitters from Reno for consideration in this feature. We’ve all seen previously what happens when they get promoted, and it’s rarely pretty. I’ve endeavored to take this generally into account when looking at the numbers, but it’s always going to be tough, especially when players have played at multiple different levels. With regard to positions, I’ve restricted each player to consideration at one spot, the place on the diamond at which they have appeared most times.

1B: Spencer Brickhouse, Hillsboro: .234/.332/.430 = .762 OPS

This is immediately a case where environment shows up. Seth Beer has a higher OPS than Brickhouse, by over a hundred points. But Beer is 17 points below the team average OPS in Reno, while Brickhouse is +97 with Hillsboro. However, it’s not exactly a great crop of prospects at this spot. You’d typically want more power. For comparison, in his age 23 season. Christian Walker put up a .846 OPS, and that was between Double-A and Triple-A.

2B: Ronny Simon, Visalia: .238/.320/.419 = .740 OPS

Switch-hitting Simon offers a good bit of positional flexibility, having started almost as many games at shortstop (20) as second (28), in addition to starts at third-base (5). The defense is still a work in progress at both middle-infield positions, with 11 errors over those 48 games. But that’s probably to be expected from a 21-year-old in his first season of American ball. He was the player to be named later, in the Andrew Chafin trade with the Cubs last July.

3B: Buddy Kennedy, Hillsboro/Amarillo: .278/.361./.464 = .825 OPS

Right-handed hitting Kennedy started off the year with the Hops in High-A, where he hit extremely well. Over 30 games, he batted 315/.386/.495 for an .881 OPS, ending in a 10-game hitting streak during which he hit .415. That got Buddy a promotion to Amarillo, where has cooled slightly, his OPS dropping back to .762 in 28 games at the Double-A level. However, the 22-year-old is young for his new league.

C: Ramses Malave, Visalia: .238/.315/.524 = .838 OPS

While I’m not sure what Ramses ate last year, it must have involved his Wheaties. In 94 games as a teenager in the Dominican Summer League, he hit just two home-runs. But he had more than that IN ONE NIGHT for the Rawhide. There seems some doubt as to whether he can stick at catcher, with most of his playing time at 1B or DH. However, he did only take up catching in November 2016, having previously been an outfielder.

SS. Blaze Alexander, Hillsboro: .212/.325/.341 = .666 OPS

Perhaps a bigger story here is the implosion of Geraldo Perdomo. A consensus top-5 Arizona prospect (top 3 in some listings), he made his major league debut in April, but was sent back to Double-A. There, Perdomo has hit just .151 over 47 games, with a .509 OPS, which is troubling. In comparison, Alexander has at least been close to team average, thanks in part to a nice 13.6% walk rate. He just turned 22, so is also young for the league.

OF. Alex Thomas, Amarillo: .268/.364/.468 = .832 OPS
Neyfy Castillo, Visalia: .245/.352/.489 = .841 OPS
Shane Garrett, Amarillo: .296/.344/.496 =.840 OPS

This list probably should have been led by Corbin Carroll, who had a 1.465 OPS over Hillsboro’s first seven games. But just as we were salivating over him, Carroll tore his shoulder while hitting a home-run swing and had to have season-ending surgery. We had also been hoping Kristian Robinson, but he has not been able to play a single game, due to his legal and mental health woes. So, we must look elsewhere. Outfield prospects tends to have a fixed position less often, so I’ve pooled all three spots there together, rather than breaking them down into left, center and right.

To start with the second spot, Castillo’s 14 home-runs in 62 games is good for third across the whole Low-A West league, not bad for a player born in 2001. Around him, we rank a pair of Double-A prospects. Garrett has generally played in left, while Thomas has started at all three outfield positions, mainly at center-field While the OPSs are similar, Garrett’s is mostly from his power. Thomas leads the Sod Poodles in walks, and his considerably younger age is what gets him the top spot in this category.

I also want to mention a couple of contenders from the ACL and DSL, though in both leagues were are dealing with VERY small sample sizes. 18-year-old Junior Franco has begun his professional career over 10 ACL games by hitting .360/.452/.560, Meanwhile in the DSL, the even younger Eskoly De Jesus (aged 17) in his first 22 PA has drawn eight walks. Here’s hoping both can continue at that pace, though I’m not prepared to do more than hope!

Starting pitching (min. 5 starts)

• Ryne Nelson, Hillsboro/Amarillo: 3.09 ERA, 96:31 K:BB in 64 IP
• Blake Walston, Visalia/Hillsboro: 3.48 ERA, 97:28 K:BB in 67.1 IP
• Matt Tabor, Hillsboro/Amarillo: 3.26 ERA, 64:24 K:BB in 69 IP
• Brandon Pfaadt, Visalia/Hillsboro: 3:38 ERA, 100:17 K:BB in 77.1 IP
• Tyler Gilbert, Reno: 3.69 ERA, 40:17 K:BB in 46.1 IP

A lot of upward mobility here, with almost all the starters here having been promoted during the season. This may be partly a result of the injury situation at the major-league level, effectively acting as a baseball waterspout, sucking up starters from the lower tiers. Walston was our top pitching prospect on the MLB.com list, coming in at #5, and has done a good job of living up to the hype this season. His age also gets him a bump, the left-hander having had his 20th birthday just last month. Nelson was considerably lower-ranked (#18), but that 13.5 K/9 rate is among the top 25 starters, across all teams and levels in the minors this season. So his stock has certainly increased sharply.

Tabor was also in the top thirty, at #21, and has handled the transition to Double-A well. Over his nine starts there, he has a 3.40 ERA and held batters below the Uecker Line, keeping them to a .199 average. Pfaadt was our fifth round pick last June, in the shortened draft, and has had a solid start to his professional career. Even after moving up to Hillsboro, the 22-year-old has been good. At High-A, he has a 3.65 ERA, with 43 strikeouts in 37 innings. Finally, while Gilbert is 27 and so hardly a “prospect”, posting a 3.69 ERA in the PCL is still worthy of applause. In fact, it’s the third-best figure in the league, among all pitchers with more than five starts.

Relief pitching (min. 15 IP)

• Mailon Arroyo, Visalia/Hillsboro: 2.36 ERA, 26:5 K:BB in 26.2 IP
• Junior Garcia, Amarillo/Reno: 2.38 ERA, 23:10 K:BB in 22.2 IP
• Mitchell Stumpo, Visalia/Hillsboro/Amarillo: 2.59 ERA, 41:9 K:BB in 31.1 IP
• Mack Lemieux, Amarillo: 2.83 ERA, 36:20 K:BB in 28.2 IP
• Miguel Aguilar, Reno: 2.90 ERA, 37:13 K:BB in 31 IP

Relief pitching is always a bit of a mixed bag; you can argue that many relievers are, to varying degrees, basically failed starters (even Mariano Rivera, who had a 5.94 ERA over ten starts in the majors!). However, you can’t say that about Arroyo, who has worked strictly out of the bullpen since moving from infielder to pitcher in 2017. The good overall figure conceals the real speed-bump encountered after his promotion. With Visalia, he allowed one earned run over 16.1 innings; in Hillsboro, six ER in 10.1 innings. Still only 23, we’ll see if he can make the adjustment. Garcia has pitched mostly for the Aces, and a 2.95 ERA there is credible, though 8 walks in 16.1 innings is higher than we’d like.

Stumpo has been promoted not once but twice. That came after a rough start, allowing five earned runs over his first five innings. But since then? A 1.37 ERA. and that includes a 1.74 figure since arriving in Amarillo in the last week of June. That is about where he should be though, as a 25-year-old. Lemieux has been striking a lot people out for the Sod Poodles, but has also been walking a lot, and that will likely need to be controled before he gets to progress any further. Last but not least, as with the starting pitchers, let’s honor a Reno pitcher who has been posting credible PCL numbers. Aguilar turns 30 in September though, so if promoted to the bigs, would be among the oldest rookies in team history!