Steve Cotterill has challenged John Utaka to score the goals to prove he can cut it as a striker.
The Blues boss remains unconvinced the Nigerian is worthy of a regular spot as one of his forwards.
Cotterill points to a Pompey record of 13 goals in 114 games as justification for harbouring his doubts.
However, Utaka has now notched in successive matches after being switched from the left-wing to a central-striking position.
The former Rennes man has long insisted operating as a striker is his preferred – and most effective – role.
But while Cotterill, right, has started to get the best out of the 29-year-old since taking over the Fratton Park reins, he doesn’t believe Utaka is prolific enough to be regularly employed as a striker.
He said: ‘John probably does favour a striking position.
‘What he would have to do, though, is produce more goals. At the moment, playing him up front depends on who we are playing more than anything else.
‘I am looking at who he will cause the biggest problems against.
‘Against Leeds, I just felt Nuge (David Nugent) didn’t have a lot of change out of their guys and thought John would offer a different problem, so I switched it just after half-time.
‘His movement is different to Nuge’s and I thought that would cause them a problem if I put him down the middle.
‘We got away with it as that worked for us at the time. Sometimes they don’t work.
‘At the end of the day, it is very difficult when you try to change your set-up within the XI.
‘But, at the moment, that is probably all I have got up my sleeve. There is nothing else.
‘John did well and scored a good goal.
‘The thing for me, though, is if he plays as a striker regularly he would have to score more goals.’
Utaka’s Burnley strike was only his third in 28 matches this season.
In fairness, the majority of those appearances have come on the left flank.
Irrespective, Utaka’s performances during four seasons at Fratton Park have failed to replicate the form which earned him a £7m transfer.
In France, he once scored successive hat-tricks against Lens and Lyon – achieved while operating as a striker.
With Dave Kitson returning from suspension against QPR next Tuesday, Utaka will face competition to keep his place up front.
But Cotterill admitted the Nigeria international’s display was one of the few bright spots in that dismal Burnley defeat.
He added: ‘Through John, we got another good goal against Burnley.
‘We don’t score scrappy ones, we always score good goals.
‘I would rather score three scrappy ones or one scrappy one and keep a clean sheet.
‘He was one of our better players that night, which isn’t saying a lot.
‘Unfortunately, in my opinion, we didn’t have any good players for the full 90 minutes.’