ORCHARD PARK, N.Y. – Rookie cornerback Rashard Robinson was diagnosed Sunday with a concussion after leaving the game in the third quarter, the 49ers announced.

Robinson made his third consecutive start on Sunday against the Buffalo Bills in place of Jimmie Ward, who has been out with a right quadriceps strain.

With Robinson out of action, Keith Reaser took over at cornerback. Dontae Johnson came into the game as the team’s third cornerback with Reaser moving inside to cover the slot receiver.

Also, the 49ers announced running back Carlos Hyde was questionable to return to action with a shoulder injury in the third quarter. With Hyde out of action, second-year player Mike Davis and Shaun Draughn shared the running back chores. Hyde returned to action after missing just one series.