Giolito was optioned to Triple-A Syracuse following Sunday's start, Mark Zuckerman of MASN Sports reports.
After a lackluster 3.1 innings in Sunday's outing, the Nationals will send their top pitching prospect back to the minors for some more seasoning. Washington will be in need of a fifth starter next Saturday, and Zuckerman named Reynaldo Lopez and Joe Ross (threw 43 pitching in rehab start Sunday) as the two potential candidates for the start. This likely isn't the last to be heard from Giolito, but he'll retake his spot in the Syracuse rotation for now. His demotion will reportedly open up a 25-man roster spot for the return of Sammy Solis (knee), who began a rehab assignment Friday.