Norman suffered the injury during team drills Thursday at Bills Stadium. He intercepted quarterback Josh Allen and was stripped of the ball by receiver Stefon Diggs during the return. Norman was slow to get up following the play but walked off under his own power before sitting out the remainder of the practice.
"We don't know the severity exactly. Those things take some time to get a good read on," McDermott said. "He'll continue to learn and be out there when he can. The biggest thing right now is that he maximizes his treatment opportunities so he can get back out there as quickly as possible."
Norman signed with Buffalo this offseason after four years with Washington. The former first-team All-Pro is expected to compete with incumbent starter Levi Wallace for the team's second starting cornerback job.