Carpenter (back) is aiming to begin a rehab assignment before the end of July, Evan Petzold of the Detroit Free Press reports.
Carpenter had a setback with his lumbar spine stress fracture in late June but resumed workouts earlier this month. He's been sidelined since late May and is without a timetable for his return, but it's looking like he won't be an option for the Tigers until at least mid-August.