Williams, who was placed on the physically unable to perform list before training camp, returned to the practice field after recovering from surgery on his groin.
"I felt a little rusty, but it feels so good to be back," Williams said. "I felt bad not being able to help my teammates out – they've been getting a lot of extra reps – so it feels good to be back contributing and taking some of the load off them."
The Panthers are still without Richie Brockel, who is recovering from a shoulder injury, and lost Jamie Childers for the season to an arm injury suffered in the preseason opener.