The Giants optioned Roupp to Triple-A Sacramento on Saturday.
Roupp's demotion clears room on the Giants' 26-man active roster for right-hander Camilo Doval, who was recalled from Triple-A. In his four major-league outings after being recalled from Sacramento on Aug. 9, Roupp allowed one run on five hits and two walks while striking out eight over 6.2 innings. He'll likely shift back into the rotation as he rejoins the Triple-A club.