The Giants optioned Luciano to Triple-A Sacramento on Wednesday, Maria I. Guardado of MLB.com reports.
After coming up from the minors in late July, Luciano went 4-for-21 with nine strikeouts over seven games. He'll now be sent back to Triple-A in order to make room for outfielder Grant McCray, but Luciano remains a top candidate to return to San Francisco should the Giants run into problems with infield depth.