Birmingham remain interested in former England international Alex Oxlade-Chamberlain after his departure from Besiktas.
The 32-year-old is available on a free transfer after leaving the Black Eagles following two years in Turkey.
Oxlade-Chamberlain is also understood to have Premier League interest while a sentimental return to Southampton - where he started his career - cannot be ruled out but strong interest remains from St Andrew's.
Ambitious Blues, promoted after winning League One with an EFL record of 111 points last season, are determined to challenge for promotion to the Premier League this term and are considering bringing Oxlade-Chamberlain in.