Rodriguez was 0-2 with a 7.65 ERA in four starts. He did not pitch after June 5 last season because of tightness in his forearm but has said since the start of spring training his arm feels fine.
Rodriguez was scheduled to start Thursday against the Reds. The Pirates did not announce a replacement.
Hughes did not allow a run in five appearances and six innings at Indianapolis, going 1-0 with three saves.