Saints are hoping Matt Targett is fit to face Burnley on Sunday after being released from the England Under-21 squad.
But Sam McQueen is reportedly on stand-by to make his first Saints start in one of the next three matches with Targett unlikely to be able to go the full 90 minutes in all of them.
Claude Puel is facing an injury crisis at left back with Ryan Bertrand likely to be sidelined for a matter of weeks with a hamstring problem that he picked up on England duty.
Targett, who has been Bertrand's main cover over the past two seasons, sustained an injury while training with the England under-21s last week.
He was left out of the squad to face Kazakhstan as a precaution, but missed out again against Bosnia and Herzegovina at Walsall on Tuesday when he had expected to be fit.
Targett was allowed to leave the squad to return to Saints for treatment.