The Padres outrighted right-handed reliever Carter Capps to Triple-A El Paso on Monday.
Capps was out of options and a 40-man spot may be needed for Chris Young, Tyson Ross, A.J. Ellis, Raffy Lopez and Adam Cimber, who are all non-roster players still in contention for a roster spot.
The Padres could place Alex Dickerson, Allen Cordoba or Colin Rea on the 60-day disabled list to help clear space.
The D-backs have set themselves up to have Ketel Marte in the middle of their infield for a while.