The Detroit Lions have made a change to their practice squad. On Tuesday, they decided to sign cornerback Conroy Black and release running back Stephfon Green. The news about Black was first reported by his agency and later confirmed by the Lions' official site.
Black actually visited the Lions back in April as part of their pre-draft visits. He didn't end up getting drafted by anybody, but he did sign with the Oakland Raiders. At the time, this wasn't a very big surprise considering Black reportedly ran a 4.3 40-yard dash at his pro day. He's got excellent speed, but the Raiders released him at the end of August. (He was let go after the Raiders played the Lions, so perhaps Detroit took notice of him on the game film afterward.)
As for Green, he was brought back as a member of the practice squad after being released during the Lions' initial wave of roster cuts. With Mikel Leshoure returning from a suspension this week and the Lions lacking depth at cornerback, they decided to swap out Green, a running back, for Black, a cornerback.