Manager Ryne Sandberg said the team has "no timetable" for Brown's return to the big league club, Ryan Lawrence of the Philadelphia Daily News reports. Brown, who was activated from the disabled list and assigned to Triple-A Lehigh Valley on Tuesday, struggled mightily during his Triple-A rehab assignment, hitting just .139 in 36 at-bats. The Phillies were not satisfied with his output, and he'll remain with the IronPigs until "he shows he's ready to make an impact for us," per Sandberg.