A few points before we get into the meat, of picking the best player at each position, including two pitchers: starter and relief. This is based on numbers put up across all levels over the course of the 2021 campaign. Factors taken into account include: level, age relative to level, park factor, playing time and pre-season expectations (more or less as a tiebreaker). A player is only eligible at one spot: this is the position on the diamond at which he appeared most often. In terms of spots here (though not PA to determine eligibility), I am combining outfield positions, with three players chosen there. However, again, I will give center fielders a bit of a boost, that being the most difficult of the outfield spots.
All clear? Good. Here we go.
C: Andy Yerzy - .220/.354/.459 = .813 OPS, 21 HR, 61 RBI
There were not a lot of credible candidates here: outside of Reno, Yerzy was the only one to reach an .800 OPS. Even those who reached .700+ tended to have issues. For example, Ramses Malave had a .746 OPS for Visalia... but also had a K-rate of over 40% (103 in 250 PA). Yerzy’s figures are particularly notable, since he played most of the year in Hillsboro, which we called “perhaps the most pitcher-friendly park in the Arizona farm system.” He also showed good plate discipline, his 53 walks ranking second across all D-backs’ minor-league players in 2021. But can he stick at catcher? Slightly less than half his total appearances were there, with 1B + DH outnumbering them.
1B: Neyfy Castillo - .230/.347/.453 = .800 OPS, 21 HR, 72 RBI
Over the past decade, only one other Arizona prospect has hit twenty home-runs in his age 20 season (Jazz Chisholm, who hit 25 in 2018). But Castillo hit 21 for A-ball Visalia, though these came with a franchise leading 170 K’s, just pipping teammate Glenallen Hill (168). Neyfy could have qualified in left as well, with 31 appearances there, as well as first. But there were no shortage of outfield contenders, while the picking at first were slimmer. Seth Beer was likely the runner up, with a .909 OPS, but that was for Reno. and we established how much that needs to be discounted for environment. It’ll be interesting to see how Castillo develops, and if he can reduce the strikeouts without sacrificing power.
2B: Ronny Simon - .245/.329/.454 = .783 OPS, 17 HR, 63 RBI
Simon did struggle somewhat after his promotion to Hillsboro, though as noted above, the environment there is unfavorable, and he was almost two years younger than the average age for the level. At Visalia, his 15 HR trailed only Castillo, and his SLG was 22 points better. Bonus credit: His 83% stolen-base success rate was fourth best on the farm (min. 20 attempts). But at this position, an interesting name to keep an eye on in 2022 might be Jean Walters. He’s a Cuban-born prospect who turned 20 in August, and hit .342 over 21 games in the ACL. His grandfather was Erwin Walters, the first MVP of the Cuban Serie Nacional. [Interview here - in Spanish, so Google Translate or Mrs. SnakePit may be helpful!]
SS: Geraldo Perdomo - .238/.357/.359 = .716 OPS, 6 HR, 35 RBI
Ryan Bliss might feel a bit robbed here, considering his full-season OPS was 58 points higher than Perdomo’s. But Geraldo was playing at a level higher, despite them being the same age. We also need to take into account Perdomo’s startling improvement over the course of this season. While his first action this year was in the majors, it was only for a week, and he struggled initially at Double-A, hitting just .151 through 47 games there, before being assigned to the Development List for four weeks. Whatever he did, apparently worked. Over 38 MiLB games before returning to the majors, Perdomo hit .329/.414/.521, a .935 OPS, and finished his year off by going 7-for-21 with the D-backs down the stretch.
3B: Buddy Kennedy - .290/.384/.523 = .907 OPS, 22 HR, 60 RBI
Kennedy’s year began as Hillsboro, where hitting .315 is not to be sneezed at. That got him a promotion to Amarillo, where Buddy’s power really flourished. After hitting five HR in 127 PA at High-A, he blasted seventeen more homers in 279 PA at the Double-A level, despite being two years below average age for the league. This is especially helpful, given third-base is a spot at which the Diamondbacks have no obvious starter at the major-league level. As Kennedy only turned 23 in October, he still might be a bit young to take over next year, but if he continues on this track, a job in 2023 is not impossible. That’d mean the team only needs to paper over the crack for one season.
OF: Alek Thomas - .313/.394/.559 = .953 OPS, 18 HR, 59 RBI
Part of Thomas’s numbers are due to him hitting .369 with a 1.091 OPS for the Aces at Triple-A. But allowing for the environment there, it’s still impressive he did that as a 21-year-old. and in center field. He was the only 2000’s born player with significant time in the PCL West this season. Even at Double-A, where he was three years younger than average, Thomas was good for a triple-slash of .283/.374/.507, an .881 OPS. There doesn’t appear to be much left for him to prove at the minor-league level, though whether the team wants to roll next with an everyday center-fielder barely old enough to vote, remains to be seen. With Ketel Marte likely returning to the infield, the job seems Thomas’s to lose right now.
OF: Dominic Canzone - .302/.375/.522 = .896 OPS, 14 HR, 52 RBI
Canzone is another player whose overall numbers seem depressed by Hillsboro - his OPS was over two hundred points better after he moved up to Double-A. For Amarillo, he hit .354/.425/.592 for a 1.017 OPS. He then finished his season with a good performance in the Arizona Fall League, where his triple-slash in 78 PA (not included in the total above) was .319/.397/.507, a .905 OPS. Having turned 24 in August, he probably should be hitting well at the Double-A level, but his numbers have been solid just about everywhere Canzone has played. Bonus credit: 19 stolen-base in 23 attempts, though oddly, those almost dried-up after his promotion out of Hillsboro.
OF: Eduardo Diaz - .255/.313/.516 = .829 OPS, 21 HR, 58 RBI
This final spot could have gone to several candidates. Down in the Dominican Republic, Junior Franco had a .923 OPS, but only over 27 games. Tim Tawa had an .857 OPS after being drafted in the 11th round this June, but again the sample size of 171 PA was a bit small. Which leaves Diaz, who had more than twice as many PA (345), and hit almost as well. Stop me if you’ve heard this before, but his numbers jumped markedly on leaving Hillsboro. Over Diaz’s 111 PA for Amarillo, his line was .316/.387/.633, a 1.020 OPS, mostly due to him hitting seven homers in just 26 games there. Stone Garrett gets an honorable mention (.825 OPS in 449 PA), but hit less well at Amarillo than Diaz, and a K:BB of 109:21 is concerning.
SP: Ryne Nelson - 116.1 IP, 87 H, 42 R, 41 ER, 16 HR, 40 BB, 163 SO, 3.17 ERA
Part of me wants to honor Tyler Gilbert. He not only pitched a no-hitter in the majors, he had a 3.44 ERA for Reno, which in the context of the PCL, is probably about a 2.00. However, 52.1 innings in the minors barely gets him into the top 30, and I am not including major-league performances here. So, we’re giving it to Nelson, whose was second for innings pitched, and had the highest K-rate of any pitcher in the system with more than 30 innings of work. While he did benefit from the Hillsboro effect, Nelson still pitched very well after promotion to Amarillo. He had a 3.51 ERA there, despite being 1.7 years younger than average, and still struck out 104 in 77 innings.
I also considered Brandon Pfaadt, eight months younger than Nelson, with a similar ERA (3.21) and more innings (131.2). They had similar ERAs at Hillsboro, but Pfaadt struggled markedly more in Amarillo (4.59 vs. 3.51) and that tilted me towards Nelson. Matt Tabor was initially in the running: through the end of July, he had a 3.60 ERA, the 22-year-old meriting a promotion first from Hillsboro to Amarillo, then to Reno. But the PCL was a nightmare: in eight starts there he had an 11.13 ERA, including 14 HR in 32.1 innings: a reset seems necessary. Finally, Drew Jameson had a decent year, with a K-rate of 11.8 and striking out better than four for every walk.
And the above was written before this:
RP: Mitchell Stumpo - 51.1 IP, 37 H, 16 R, 15 ER, 6 HR, 13 BB, 66 SO, 2.63 ERA
Coming into the season Stumpo was approaching his 25th birthday, and hadn’t played above rookie ball. Part of that wasn’t his fault, 2020 having been canceled, but he had been undrafted out of college, and his rookie numbers were merely decent. But Stumpo made up for lost time this season, blazing through A, A+, AA and AAA, ending the season in the Arizona Fall League. A 1.08 ERA at Hillsboro obviously helped, but he followed that up with a 2.59 for Amarillo and a 1.50 in Reno. Small sample size for the latter - just six innings - but I’d not be at all surprised to see him bid for a bullpen spot in spring training. If he’s not on the roster for Opening Day, he should be there not long into the 2022 campaign.
A few honorable mentions seem appropriate here. Mack Lemieux had a 3.35 ERA over 45.2 innings, mostly with Amarillo, and struck out 58 batters, though also walked 28. But there were less than a handful of others who made 25+ appearances and also had an ERA below four. The youngest of these was 22-year-old left-handed Venezuelan Liu Fuenmayor, who feasted in Hillsboro, where he had a stellar 27:2 K:BB across 17.1 innings. Veteran minor-leaguer Junior Garcia, who turned pro in 2013, was arguably Reno’s best reliever, with a 3.94 ERA there over 32 innings, credible PCL numbers. And Mailon Arroyo struck out more than a batter per inning in A and A+, with a 42:7 K:BB ratio.