Thurmond is the latest former Oregon player to join the Eagles since coach Chip Kelly left the Ducks two years ago. He spent his first four seasons with Seattle and played two games for the New York Giants last year before a torn pectoral ended his season.
The 27-year-old Thurmond has started nine games in his five-year career. He joins a secondary that's replacing three of its four starters. Cornerback Byron Maxwell already was signed away from the Seahawks.
Sanchez agreed to a contract on Sunday. Sanchez set a franchise record with a 64.1 completion percentage and threw for 2.418 yards with 14 TDs and 11 interceptions, going 4-4 as a starter in his first season in Philadelphia.
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