Gamboa will remain with the Red Sox after serving as the 27th man during Wednesday's doubleheader against Baltimore, Ari Alexander of 7 News Boston reports.
Gamboa was originally expected to return to Triple-A Worcester after the conclusion of Wednesday's twin bill, but it'll instead be Eduardo Rivera who heads back to the minors to get Boston back within the 26-man limit. Gamboa pitched a scoreless inning Wednesday to bring his ERA down to 2.00 through nine frames, but he's likely to remain in a middle-relief role with Boston for now.