Robets (shoulder) will report to Triple-A Iowa on Sunday to begin a rehab assignment, Tony Andracki of Marquee Sports Network reports.
Roberts recently threw a live batting practice session, which was his final hurdle before being cleared for game action. The 24-year-old has been sidelined by shoulder inflammation since late April, so he'll likely require at least a couple appearances with Iowa before being reinstated to the big-league roster.