Bell (hamstring) will "be down for a little bit," according to head coach Dan Campbell, Dave Birkett of the Detroit Free Press reports.
Bell suffered the injury during practice last Thursday and still isn't quite ready to return. The San Diego State alum joined the Lions as an undrafted free agent this spring and was likely facing an uphill battle to make the squad. Any significant time missed will likely hurt the 24-year-old's chances of earning a spot on the Lions.