Last week the Red Sox DFA’d relief pitcher Connor Seabold, bringing an end to his time in Boston. They’ve now made a corresponding move that will net them a return.
Designating a player for assignment is not an outright release. What it does is remove that player from the 40-man roster, and then starts a seven-day clock for the team to either trade that player or place him on irrevocable waivers. If the player clears waivers, he can be reassigned to the minor leagues or released all together.
In Seabold’s case, the team needed to open up a spot on the 40-man to make room for the recently-signed Corey Kluber. That move was made official last Thursday.