Will the next Rule 5 draft impact today’s roster decisions?

Stats that are mentioned in this article were retrieved on May 2nd so data will have changed, but I assume that the overall picture is still valid.

Normally we discuss the Rule 5 draft in November, when it is close to happening. But recently there was a minor discussion on this site that the next Rule 5 draft could already influence this season’s roster decisions.

So, maybe a bit earlier than normally, but who are the most prominent players that will be subject to the Rule 5 draft in the following off-season?

We start with players that are ranked on the prospect lists of MLB Pipeline and FanGraphs (in a future I will add more Diamondbacks’ prospect rankings). Note that the following kids were all already Rule 5 eligible last season.

Dominic Canzone (26), OF, #20 on MLB Pipeline (2023), #31 on FanGraphs (2022) - Reno (AAA)

Canzone slipped through the Rule 5 draft as teams were not impressed by his .838 OPS in Reno in 2022. Canzone enters his 26th year and looks like a lock to either get added to the 40-man roster this off-season or get picked by a team, after seasoning another year in AAA. In almost 100 PA so far in Reno he has cut a bit back on the strikeouts and added a few more walks so if he continues that trend he should get a late call-up this season to show if he can be another depth piece in that crowded outfield the team can count on.

Neyfy Castillo (22), 1B/OF, #31 on FanGraphs (2022) - Amarillo (AA)

Castillo was a 16-year old international signing in 2017 although he didn’t make his first pro appearance, in the DOSL, until 2018. He has played on both corners of the infield although the righty is rather deployed in the outfield. The Dominican is dubbed as a power-bat but struck out at a huge 30%+ clip in Hillsboro last season. He has started the season in Amarillo but the strikeout-issues have worsened, as could have been expected. With a .435 OPS in one the most friendliest hitter parks, he could be up for a demotion and plays no role in any Rule 5 decision.

Wilderd Patino (22), OF, #14 on MLB Pipeline (2023) - Hillsboro (A+)

Patino didn’t dress to impress last season in Hillsboro, where a healthy batting average of .288 was able to disguise the bad rates in strikeouts and walks. He is repeating at High A again but has a rather slow start to the season. MLB Pipeline is pretty high on Patino because of the speed and the speed is real, with already 13 stolen bases this season so far. He currently leads all Diamondbacks’ minor leaguers in that stat so he is a player to keep an eye on. But he is probably too far away from the major leagues to be considered an addition to the 40-man roster come December.

Alvin Guzman (22), OF, #22 on FanGraphs (2022) - Visalia (A)

“Low-probability prospect with a cathedral ceiling”, that is how FanGraphs characterises the Dominican 2018 international signing. Guzman is laureated for his speed and the power potential, but while he did contribute quite some in the stolen bases column, the power was not visible in Visalia last season. The outfielder repeats at that level again, and is showing some signs of progress but the 31 strikeouts in 75 plate appearances is a huge stopper.

Mitchell Stumpo (27), RP, #40 on FanGraphs (2022) - Reno (AAA)

Stumpo was one of those Diamondbacks who shone on the World Baseball Classic. He finally looked like the pitcher that could throw himself into the Diamondbacks bullpen. He threw a good amount of strikes in 2022, but had troubles limiting the walks. In Reno he was supposed to work on that before getting a call-up to make his major league debut later this season, but a couple of weeks into the season and things have gone terribly sour in Reno for Stumpo. He has given up a ton of hits, homeruns and walks and will have to start all over again. On April 22 the Diamondbacks moved Stumpo to the Development List. He was recently activated again, but hard to imagine that Stumpo will be a name to consider ahead of the Rule 5 draft.

Conor Grammes (26), RP, #28 on MLB Pipeline (2023), #20 on FanGraphs (2022) - Hillsboro (A+)

Conor Grammes is a name that has surfaced a bit in the lower tiers of the prospect rankings but each season it seems more and more a question of if he will make the majors than when. At 26 years of age Grammes hasn’t reached AA yet, although he also underwent TJ surgery in 2021. The strike potential and stuff has kept Grammes on the prospect list of FanGraphs, but the walks will probably limit him in exploiting his potential and early news from Hillsboro, where he repeats again, confirms that.

Levi Kelly (24), RP, #40 on FanGraphs (2022) - Hillsboro (A+)

Kelly was still on the Diamondbacks top prospects list of FanGraphs in 2022, but good chance he won’t be back in the next list. Injuries and mechanical issues have hampered Kelly’s development severely since the pandemic happened, Tabor-like, but the pitcher is still only 24 years old, so all isn’t lost yet. Kelly was taken in the 2018 MLB amateur draft and will enter his second year of Rule 5 eligibility. Last year he pitched just 1.1 innings and some early news out of Hillsboro doesn’t make us believe that he is back on development track: a 15.6 BB/9 and 11.4 H/9 is an alarming stat, even after just 6.1 innings of pitching. It is more likely Kelly won’t be in the organisation in 2023 than him being added to a 40-man roster.

Yaifer Perdomo (22), RP, #43 on FanGraphs (2022) - Visalia (A)

Perdomo is another one of those strike-throwers FanGraphs loves so much. Perdomo struggled mightily in Visalia last year, although he did show durability with that arm, pitching 74.2 innings in California, but being tagged with 57 runs. Having started in the early years, the Diamondbacks have him now committed to pitching in relief. That has resulted in a terrific 15.9 K/9 in 11.1 innings in 2023, but Perdomo is still terribly wild from time to time. However, he is an interesting high-risk profile to keep an eye on but won’t be in the discussion for 40-man roster decisions.

Other ball players.

Tristin English was a 2019 MLB amateur draft pick who has slowly moved up the ladder and will probably earn a mid-season promotion to Reno. He struck out less than 20% last season and has good hit and walk rates. It is a bit of a tough profile to fit in as he isn’t a power bat nor does he have any speed. Hard to see him getting picked by a team in the Rule 5 draft so the Diamondbacks probably won’t need to protect him.

Listher Sosa was one of few pitchers in Visalia last year who actually had something of a decent season, pitching to a 3.42 ERA in 68.1 innings. He isn’t much of a strikeout guy but in 14.2 innings so far has really cut down on the walks, making him one of few Rule 5 kids with average to good walk rates. He did hit 4 batters though, so some wildness is there, but could be a name to remember although not for the 40-man roster.

Last but not least, and I am biased here – you are warned, Eric Mendez has had an excellent start to the season in Visalia. In a small sample size of 7 innings (4 games), the Aruban pitcher who played for The Netherlands at the WBC has allowed just 2 runs and has an excellent 5.5 K/BB. That is a terrific improvement over his 1.31 K/BB from last year. Although his current pace might not be sustainable, Mendez is surely up for promotion soon and he could be one of those underrated kids to make a note of. Just not for the 40-man this season.

So, there you have an assessment. I’d say the 40-man roster crunch won’t exist this season as there isn’t that much talent that has to be protected, so I don’t see this year’s crop forcing the front office to make some early decisions because of them. It could very well be that last season’s Rule 5 draft urged the Diamondbacks a bit more in protecting talent, foreseeing that this year’s list was going to be much shorter.

Please note that there are many more Rule 5 eligible players in the organisation, like Dominic Miroglio, but I highlighted those that are most prominent according to status and current results.

Now share your view with us!