Douglas (ankle) was released by the Giants on Tuesday, Michael Eisen of the team's official site reports.
Douglas played all 66 offensive snaps during the Giants' final exhibition game Sunday after missing time with an ankle injury this preseason, but this was not enough to secure his spot on the team's final 53-man roster. The 30-year-old offensive lineman played 33 games between Tennessee, Buffalo and Washington over the past three years, and he will now likely look to carve out a reserve role on a practice squad or active roster elsewhere this season.