METAIRIE, La. - The New Orleans Saints have placed P.J. Williams on injured reserve, three days after the cornerback absorbed a hard hit to the head during Sunday's loss to the New York Giants.

Williams, whose designation was posted on the NFL's transactions listings Wednesday, took a knee to the helmet in a collision with Giants tight end Larry Donnell.

Williams was able to move his extremities, but was immobilized, carted off the field and taken to a hospital.

On Monday, Saints coach Sean Payton said Williams had a concussion, but otherwise called the cornerback's prognosis "real encouraging."

Williams, a 2015 third-round draft choice, spent his entire rookie season on injured reserve with a hamstring injury. Now his second season has ended after two games.

The Saints have added offensive tackle Tony Hills to their active roster.