To make room, the Nationals designate Fernando Abad and Tyler Robertson for assignment.
Both pitchers are taken off the 60-day disabled list and the Nationals roster now stands at 40 players.
The Nationals protected two right-handed pitchers by adding them to the 40-man roster before the Rule 5 draft deadline.
A rundown of players the Nationals might add in anticipation of the Rule 5 draft on Dec. 6.
The Nationals have several players they will have to consider adding to their 40-man roster or risk them getting taken in the Rule 5 draft.