Davis was blocking on the return when he went down at about the Detroit 17.

Davis was down for several minutes, during which trainers unscrewed the face mask from his helmet. He was placed on a board, then lifted onto the back of a truck.

There was no immediate word about his injury.

Players from both teams stood on the field silently, some bending to one knee.

Davis is a six-foot-three, 325-pound undrafted free-agent from South Florida who was signed by the Lions on May 4.