Soto Shuts Up Talking Stick at Salt River Fields

HAGSAG: Just like there is a Reserve List limit for MLB clubs (the so-called "40-man roster"), there is also a Reserve List limit for minor league clubs, too:

IOWA (AAA): 38 (25-man Active List) 
TENNESSEE (AA): 37 (25-man Active List)
DAYTONA: 35 (25-man Active List)
KANE COUNTY: 35 (25-man Active List)
BOISE: 35 (30-man Active List - 25 designated "active" for any given game of which at least 10 must be pitchers)
AZL CUBS: 35 (35-man Active List - 30 players designated "active" for any given game of which at least 10 must be pitchers)
DSL CUBS: 35 (35-man Active List - 30 players designated "active" for any given game of which at least 10 must be pitchers)
VSL CUBS: 35 (35-man Active List - 30 players designated "active" for any given game of which at least 10 must be pitchers)

So the 60-day DL is essentially used the same way in the minors as it is in the big leagues, to create additional slots on a minor league affiliate's Reserve List during the season if the affiliate's Reserve List is full. (The one difference is that an MLB player can be placed on a club's 60-day DL beginning with the start of Spring Training as long as the MLB club's 40-man roster is full, but minor league players cannot be placed on a 60-day DL until Opening Day). 

When players are signed after being selected in the MLB Rule 4 Draft (AKA "First Year Player Draft") and the player signs a contract for that season, the player must be placed on a minor league affiliate's Active List or Disabled List within 20 days after the contract is signed, but the player does not count against the minor league club's Reserve List until the Reserve List rosters are filed in November. 

And players who are "Signed for Future Service" (player signed after July 1st and first contract is for the following season) cannot be placed on a minor league affiliate's Active List and do not have to be placed on the minor league affiliate's Reserve List until Opening Day of the following season, even though the player can participate in a post-season Instructional League, Minor League Camp, and Extended Spring Training. So for example, Gleyber Torres was "Signed for Future Service" last July and so he is not presently on a minor league Reserve List. but he will have to be added to the Reserve List AND Active List (or DL) of whatever affiliate he is eventually assigned beginning on Opening Day of that affiliate (whether it be Boise, AZL Cubs, or VSL Cubs). Same goes for Eloy Jimenez, Johan Matos, Erling Moreno, et al.

Because players selected in the June draft who are not Signed for Future Service (which are almost all of the drafted players who sign) must be added to a minor league affiliate's Active List or DL within 20 days of signing, the roster crunch for Boise and the AZL Cubs during the season relates to the affiliate's Active List, not its Reserve List. So (for instance) when the AZL Cubs place a player on its 60-day DL during the AZL season, its because the AZL Cubs 35-man Actve List is full, not because its Reserve List is full.    

Also, even though the Iowa Active List presently includes about a dozen players who are on the Cubs MLB Reserve List (Chris Rusin, Matt Szczur, Josh Vitters, Arismenmdy Alcantara, et al), the AAA Iowa Reserve List is usually full or nearly-full because of the number of players who were assigned to the Iowa roster the previous November (prior to the Rule 5 Draft) to exempt the player from selection in the minor league phases of the Rule 5 draft (there are no roster restrictions or right to re-claim players lost in a minor league phase of the Rule 5 Draft, so if there isn't room for a prospect on the MLB 40-man roster in November, the next-best thing is to place the player on the AAA affiliate's Reserve List--its "38-man roster"-- so that he will only be eligible for selection in the Major League Phase of the Rule 5 Draft), even though the player might presently be on the Tennessee, Daytona, or KC Active List.