Kenwyne Jones will today have a scan on the ankle injury which forced him out of the game at Preston.
The Saints striker limped off midway through the second half at Deepdale and left the ground on crutches.
An X-Ray has shown there is no break but the club are now checking to see if there is ligament damage or bruising to the bone.
It makes Jones doubtful for Saturday's trip to his old club Stoke where he spent a successful loan spell two seasons ago although he has not yet been ruled out.
Saints though could welcome back two recent casualties for the game at the Britannia Stadium where tickets are only available on the day, not in advance.
Alexander Ostlund and Darren Powell are both back in full training and if there is no reaction both could be in Saturday's squad.
That leaves Michael Svensson as the only long-term injury and the club are currently investigating other options after homeopathic injections failed to cure the knee problem.