Bills leading WR Stevie Johnson leaves practices after injuring left hamstring

PITTSFORD, N.Y. – Buffalo Bills wide receiver Stevie Johnson left practice after injuring his left hamstring Friday morning.

Johnson, Buffalo's top receiver, pulled up on a route during a red zone drill two hours into practice. He was evaluated by Buffalo's training staff and walked slowly to the locker room assisted by two people.

Bills coach Doug Marrone said after practice that he did not know the severity of the injury and that Johnson will be evaluated by Buffalo's doctors.