MLive will preview each of the Detroit Lions' position groups heading into the start of training camp on July 27. Today: Secondary. Previously: Running back | Quarterback | Offensive line | Receiver/tight end | Defensive line | Linebacker
Roster locks: CB Darius Slay, CB Teez Tabor, CB DeShawn Shead, CB Nevin Lawson, CB Jamal Agnew, CB/S Quandre Diggs, S Glover Quin, S Tavon Wilson, S Tracy Walker
Competing: CB Mike Ford, CB Chris Jones, CB Antwuan Davis, CB Amari Coleman, S Miles Killebrew, S Rolan Milligan, S Stefan McClure, S Charles Washington
Notable departures: D.