Robert (thumb) was sent to the AZL White Sox to start a rehab assignment Tuesday, James Fegan of The Athletic Chicago reports.

EDGE Analysis

Robert was expected to miss 4-to-8 weeks after suffering a sprained left thumb at the end of June, so he's currently on track for a return in the front half of that timetable. The expected length of the rehab assignment remains unclear and the young outfielder -- who turns 21 on Friday -- could return to High-A Winston-Salem in early August, but the White Sox are likely to remain cautious as he returns from his second left thumb injury of the season.