The Rangers optioned Harris (oblique) to Triple-A Round Rock on Tuesday.
Harris received an invite to big-league camp as one of the organization's top prospects and went 3-for-10 with a double and two RBI through five games, but he's been sidelined by an oblique issue for the past week. The 24-year-old didn't have a realistic chance of making the Opening Day roster regardless of the injury, and he'll now shift over to minor-league camp.