Jefferson will miss some practice time due to an ankle injury, Kyle Meinke of MLive.com reports.
Coach Dan Campbell said the Lions "do not think it's serious" with regard to Jefferson's injury, adding that "it doesn't look like it's a high ankle [sprain]." That said, it's looking like the rookie seventh-round pick's availability for Friday's preseason game against the Bills could be in danger. If Jefferson can't go Friday, or is limited, all of Dedrick Mills, Michael Warren and Godwin Igwebuike will be candidates to see increased work.