Pompey are sweating on the fitness of Simon Ferry ahead of the trip to Mansfield.
The midfielder came off with a foot injury in the win over Morecambe at the weekend.
His 55th-minute withdrawal was prompted when a Shrimps player stamped on his toe.
Ferry, a free transfer from Swindon, was seen by an orthopaedic doctor after the final whistle of the impressive 3-0 victory for Guy Whittingham’s men.
The toe problem has since ruled the former Swindon player out of training and he faces a battle to make Saturday’s Field Mill fixture.
His injury comes at a time when Johnny Ertl returns to the Blues squad following suspension.
Last year’s The News’ Player of the Season has sat out the past three matches following his sending off against Oxford. In his absence, Romain Padovani has come in to partner Ferry in the centre of midfield, impressing in the process.
Now Ferry is struggling to overcome his toe injury and that could let Ertl back into Whittingham’s side.
Pompey’s medical team will monitor Ferry during the remainder of the week in the hope his injury responds positively to treatment.