Luciano was removed from Tuesday's game with Triple-A Sacramento due to a hamstring injury, Susan Slusser of the San Francisco Chronicle reports.
Luciano's removal from Tuesday's game was initially expected to be a sign of a promotion to the majors, but it seems Luciano was instead battling an injury. Luciano is slashing .244/.320/.422 in Triple-A and went 3-for-11 during his first MLB stint, so a return to San Francisco could be in the cards for Luciano after he recovers.