Porter signed his contract Saturday morning, making him the latest addition to the Redskins defense during free agency.
The Redskins have been seeking a replacement for Josh Wilson, who is a free agent. Porter is expected to compete with second-year player David Amerson for the starting cornerback job opposite DeAngelo Hall.
Washington this week has also added defensive linemen Jason Hatcher and Clifton Geathers and linebackers Darryl Sharptons and Adam Hayward.
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