The Redskins added Ihenacho on Sunday, a day after he was let go by the Broncos.
Ihenacho started all but one game for Denver last season and made nine tackles in the Super Bowl loss to the Seattle Seahawks, but the third-year player was the odd man out this preseason in a crowded secondary that includes Quinton Carter and free agent acquisition T.J. Ward.
The Redskins are thin at safety, in part because of Brandon Meriweather's two-game suspension for a helmet-to-helmet hit.
To make room for Ihenacho, Washington waived undrafted rookie safety Akeem Davis. Davis is a likely candidate for the practice squad if he is not claimed by another team.
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