Peguero (hamstring) began a rehab assignment with Triple-A Sacramento on Tuesday, walking all three batters he faced and getting charged with three runs.
It certainly wasn't the result Peguero was looking for, but he could be a bit rusty given that it was his first game appearance since late May. The righty reliever is working his way back from a strained hamstring and will need a few more rehab outings before rejoining the Giants' bullpen.