After reportedly failing to settle to life in the north-east, Gardner could be in the frame for a move back to his boyhood club, having left St. Andrews last summer to join Sunderland in a move that was worth £4.7 million.
The 25-year-old impressed last campaign, bagging eight league goals from midfield in a struggling Birmingham outfit that were ultimately relegated on the final day of last season.
However, he has failed to make any sort of lasting impression since his move to the Stadium of Light, and a potential short-term loan switch has been mooted.
Chris Hughton has not yet given up hope of striking a deal, despite being rebuffed in his attempts to take back Gardner by new Sunderland boss Martin O’Neill.
“When the window closes, there will be some Premier League clubs that have players who are not getting regular games who will be surplus for whatever period," Hughton said.
“We still have that open to us. Maybe a month on a short loan."