Carpenter (back) ran the bases at Comerica Park on Thursday, Chris McCosky of The Detroit News reports.
Running the bases is often the final box a player needs to check before they go out on a rehab assignment, so it's certainly a good sign for Carpenter. The outfielder has been sidelined since late May with a lumbar spine stress fracture, and because he's missed so much time he'll probably require more than just a couple rehab games.