Rangers midfielder Harry Forrester is available on a free transfer after being told he is no longer wanted at Ibrox.
The 26-year-old turned down a move to League One side Southend earlier this summer because he believed he had a chance under Pedro Caixinha.
But the Portuguese manager has told him to find another club and Forrester is hoping for a move to the Championship.
He is also open to offers from League One and Charlton have previously expressed an interest.
Forrester was signed by former Rangers manager Mark Warburton, having worked with him at Brentford before he joined Championship side Doncaster.
The former England youth international has made 44 appearances for Rangers and scored eight goals.