Arizona is looking for 1-2 quality major league ready or near-ready bullpen arms, no matter what you call them: closer/setup/stopper/LOOGY/whatever. The following players could be moved for the right player(s):
RH SP Carl Deer: Rated top-100 prospect by OSA, second round draft pick in 2016, currently at double-A, Deer is almost ready for the majors. 4 pitches, decent gas, groundball mechanics.
C Dwight Childs (ML): some power, capable backup catcher.
RF/CF/LF Che-Hsuan Lin (ML) -- gold glove caliber defensive outfielder.
1B/3B Alex Santana (AA) -- capable corner infielder, power potential.
RH RP Conner Sadzeck (ML) -- might benefit from a change of scenery.
SS/2B Daniel Santana (ML): solid glove off the bench.
RH RP Joel Lima (ML) -- solid reliever, could swap for a younger relief prospect.
1B/2B Alfredo Zavala (ML) -- bench bat, decent glove, good baserunner.
RH SP/RP David Perez (ML) -- three pitches, groundball pitcher.