White Sox select Moises Castillo, sign Yacksel Rios in biggest December moves yet

KANSAS CITY, MO - JUNE 18: Boston pitcher Yacksel Rios (75) on the mound against the Kansas City Royals in the game against the Kansas City Royals against the Kansas City Royals on June 18, 2021, at Kauffman Stadium in Kansas City, Missouri. (Photo by William Purnell/Icon Sportswire)

The minor-league phase of the Rule 5 draft usually makes no waves, but the White Sox have developed a couple of selections over the past decade that make every year’s names worth writing at least once.

In 2013, the White Sox nabbed Omar Narvaez from the Tampa Bay Rays, and he’s been a starting catcher at the MLB level for five years running. Four years later, the White Sox picked Yermín Mercedes from the Orioles. He only gave the White Sox one good month before it all fell apart, but the month was of vital importance, as he supplied the White Sox with league-best production out of the DH spot for the first several weeks after the late-spring injury to Eloy Jiménez.

The picks since Mercedes show why this part of the MLB offseason mostly goes overlooked, but with transactions involving major-league players at a standstill thanks to the lockout, the minor-league phase finally gets its time to shine in the December sun.

The White Sox played their part by selecting shortstop Moises Castillo from the Cardinals with the 23rd pick.

Castillo’s a lifetime .239/.329/.327 hitter over 294 minor-league games since St. Louis signed him for $140,000 during the 2015-16 international signing period. Here’s Ben Badler’s description from the time of the signing:

Dominican shortstop Moises Castillo landed a $140,000 bonus when he turned 16 on July 14. Castillo is a high-energy player with some similarities to Cardinals shortstop Edmundo Sosa. He’s 6-foot-1, 170 pounds with good bat-to-ball skills from the ride side, albeit with limited power right now with more strength one of his greatest needs. He will likely split time between shortstop and second base, possibly fitting better at second with fringy arm strength and speed.

His most notable asset is consistency, although that’s not what you want to see from a player with years of development ahead of him. Each season more or less looks like a photocopy of the one that came before:


He’s also not much of a basestealing threat (22-for-30 in his career), and while he’s managed to stick at shortstop, errors have bunched up on him there (15 over 64 games).

Then again, you wouldn’t expect a scintillating profile for a guy available in this pool. Previous selections include Martin Carrasco, who went 1-8 with a 5.85 ERA for Kannapolis in 2021, and Will Carter, who posted a 5.02 ERA and a 1.70 WHIP at Charlotte.

One player with name recognition found a new home in the minor-league phase, but he’s not one White Sox fans would want. The Dodgers selected Carson Fulmer away from the Cincinnati Reds.

It’s been a long fall for Fulmer since the White Sox designated him for assignment before the start of the truncated 2020 season. He was first claimed by the Tigers, after which he spent time in the Baltimore, Pittsburgh and Cincinnati organizations. It was worth keeping occasional tabs on his last stop, as it reunited him with Driveline Baseball founder Kyle Boddy, who was the Reds’ pitching director at the time. He threw his curveball more than ever, but his fastball still languished in the low-90s.

Given all the velocity jumps the Reds made elsewhere in the organization, it’s hard to say the Dodgers will have any better ideas. Perhaps a reunion with Vanderbilt rotationmate Walker Buehler is what he’s been missing.

More notably than the player gained, the White Sox didn’t lose anybody in this part of the Rule 5 draft. Baseball America had identified A-ball outfielder Alex Destino as a possibility, which again reflects the distance from the majors most of these players are.

The last player the White Sox lost in this phase was A.J. Puckett, who only threw five games for Winston-Salem after coming over from Kansas City in the Melky Cabrera trade. He lost the remainder of the 2017 season to elbow problems, along with the entirety of the 2018, 2019 and 2020 seasons. He finally resurfaced in the Atlanta organization this past year, posting a 2.90 ERA over 80⅔ innings split between High-A and Double-A in his age-26 season.

* * * * * * * * *

The White Sox made another minor move in all regards earlier this week by signing right-handed reliever Yacksel Rios to a minor-league deal, according to the team’s transactions page. Rios has appeared in 89 games over five seasons for four different teams, posting a 5.77 ERA and striking out 91 batters against 50 walks over 96⅔ innings.

Rios, 28, was last seen with the Red Sox in 2021. He went 3-0 with a 3.70 ERA over 20 games, and reached new heights by averaging 97 mph with his fastball. The Red Sox still DFA’d him in September, perhaps because of the lackluster 21.4 percent strikeout rate and the wholly unsustainable .169 BABIP. He does have baseball’s fifth-highest pop-up rate among pitchers to throw 30 innings the last two seasons, and he’s started throwing his splitter more, so an optimist would say he’s circling around an arsenal that sticks. The velocity is why he keeps getting chances.

From here, the question is whether Rios and Castillo are the two biggest additions made by the White Sox during the month of December. If so, one hopes it’s because of reasons that are just 1/30th within their control.

(Photo by William Purnell/Icon Sportswire)


  • Jim Margalus

    Writing about the White Sox for a 16th season, first here, then at South Side Sox, and now here again. Let’s talk curling.

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Joliet Orange Sox

I am of course thrilled by these moves. I’m concerned how I will explain to my boss when I don’t get anything done the rest of today due to my excitement.


Don’t sweat it. Your boss was probably so breathless over the same news, that your productivity never got noticed.

Augusto Barojas

Clearly they are better than the Astros after these moves.


I wonder how many former major league players are taken in the rule 5 minor league draft (meaning they are not minor league free agents and not on an AAA roster). I’m guessing it’s somewhat unusual? Also, Fulmer wasn’t taken until the 39th pick, which makes him closer to the end of the draft than the beginning.

Also, the White Sox missed out on a guy named Walking Cabrera. https://www.fangraphs.com/players/walking-cabrera/sa3005240/stats?position=OF
He did have a decent walk rate in complex league this year, if you’re wondering.


If his surname were Taco, the Sox would have grabbed him.

Trooper Galactus

Carson Taco?


Jace Fry, Jake Burger, Taco Cabrera. We just need to find a way to trade for Seth Beer to continue our all fast-food lineup.


That headline would be the definition of damning with faint praise if anyone who didn’t understand the context was expected to read this.

Last edited 2 years ago by soxfan

Is there no plan/value for Mercedes? He has hit at every level, even back in 3 A after his demotion. He’s just hanging out to dry in the White Sox system. I can’t remember a White Sox player ever going on a hitting tear like we witnessed in April-May. Perhaps he’s not coachable to address the hole(s) in his swing, but it sure would be worth someone trying.


Yermin is on the 40-man, so he’s locked out too, they can’t do anything even if they wanted. I think he has a little trade value to a NL team newly in need of a DH, assuming that’s part of the new CBA.

Because once big league pitchers figured him out, he didn’t have an answer. As epic a tear as he went on, he finished the season with an exactly league average OPS+ of 100. In the last month and a half before he was demoted (May 14-June 30) he posted a .496 OPS, and no, that is not a typo. Being a DH-only player who has an easily exploited swing doesn’t make for a useful player.

Last edited 2 years ago by Trooper Galactus
To Err is Herrmann



The Sox organization is a happier place with a Moises as an active player.

Right Size Wrong Shape

I was thinking the same thing!

As Cirensica

So, what does this say about Romy? Don’t the White Sox need to place Moises in the 26-man roster?

As Cirensica

Hmmm… Sometimes I am confused about the rules. When is it that a team claims a player and must place him in the active roster?

Per MLB:

A team that selects a player in the Rule 5 Draft pays $50,000 to the team from which he was selected. The receiving team must then keep the player on the Major League 25-man roster for the entirety of the next season, and the selected player must remain active (not on the disabled list) for a minimum of 90 days. If the player does not remain on the Major League roster, he is offered back to the team from which he was selected for $25,000. If his original team declines, the receiving team may waive the player.

Once a player is selected, he is automatically assigned to his new organization’s 40-man roster.

I guess there are two types of Rule 5 drafts, and I didn’t know that. Hmmm

As Cirensica

Thanks. Learned something new.