Sosa (wrist) had hamate bone surgery in June and has begun rehabbing, Kyle Glaser of Baseball America reports.
The average return time for an injury like Sosa's is 4-to-6 weeks, but it is unclear how well the shortstop is following that timetable as the Cardinals haven't announced a formal return date. Sosa has spent most of his time this season with High-A Palm Beach but appeared in one game with Double-A Springfield before suffering the injury.