Amerson is listed as questionable for Sunday's game against the Tennessee Titans.
Coach Jay Gruden said Friday that Amerson ''is on a positive track'' to play but has to be cleared through the NFL's concussion protocol.
Without Amerson, the Redskins would be without their top three cornerbacks. DeAngelo Hall is out for the season with a ruptured Achilles tendon, and Tracy Porter remains sidelined with an injured right hamstring.
Gruden said quarterback Robert Griffin III took a few more snaps in team drills and is ''slowly but surely getting back into the flow.'' Griffin returned to practice this week from a dislocated left ankle. He has been ruled out for Sunday's game.
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