Although the Detroit Lions did agree to a deal with linebacker Justin Durant, that isn't expected to be the only move at the position. With one starting job still open, people are anticipating the Lions to make another move involving a linebacker.
The hope is that the Lions end up signing someone like Stephen Tulloch or Nick Barnett, but if things fall through with both of them, perhaps Chargers linebacker Brandon Siler will be an option. From Dave Birkett:
The Lions have some interest in LB Brandon Siler. Nothing imminent, but he could join Levy and Durant.
This seems like one of the backup plans for sure. I think Tulloch is Plan A and Barnett is Plan B, so Siler could be an option the Lions revisit later on if nothing develops with other linebackers.