It was on very short notice — Monday night’s game was postponed only about 12 hours ago — but Justin Hancock was brought to Chicago from Triple-A Iowa to be the 26th man for the day-night doubleheader Tuesday:
The “26th man” must be on the club’s MLB Reserve List (40-man roster) or has to be added to the club’s 40-man roster that day.
The “26th man” does not have to be a pitcher.
In the case of a doubleheader that is scheduled at least 48 hours in advance, the 26-man Active List limit is in effect for both games of the doubleheader, but the “26th man” cannot be switched between games.
The player who was recalled as the “26th man” can remain on the Active List and a different player can be dropped the next day, as long as the “26th man” was not called up prior to spending at least ten days on optional assignment. NOTE: A player called up as the “26th man” prior to spending at least ten days on Optional Assignment could remain on the 25-man roster if the player replaces a player who is placed on the Disabled List (or other MLB inactive list) the day after the doubleheader.
If a player is recalled as the “26th man” and is optioned back to the minors the next day, the “10-day rule” clock (prohibiting a player from being recalled until he has spent at least ten days on Optional Assignment, unless he is replacing a player who is placed on the DL or other MLB inactive list) does not start over again. However many days toward ten that the player spent on Optional Assignment prior to being recalled as the “26th man” counts.
A player recalled as a “26th man” accrues one day of MLB Service Time.
Hope this explains it all better.