But the Blues are refusing to put all their eggs in one basket and have several other left-backs on their radar.
Cam Pring’s recall to Bristol City means Lee Brown is the only senior left-sided defender at Fratton Park – increasing the need for a new addition.
Pompey are keen for Seddon to return for a second spell at Fratton Park following his scintillating loan spell during the second half of last season.
The fans’ favourite is back at Birmingham after spending the first half of this campaign at AFC Wimbledon.
The Blues tried to sign Seddon on a permanent basis last summer, only to be put off by Brum’s unreasonable price tag.
Recent developments mean Pompey’s interest in the Reading lad has reignited during the January transfer window.
However, Jackett insists there are others full-backs on his shopping list.
‘It’s a specialist position and not somewhere you want to be short,’ the Blues boss told The News.
‘We are and we will be looking for another specialist left-back to compete with Lee.
‘Steve came here and obviously did well last season. There are a number of players we are looking at but don’t have one we are close to.
‘We were interested in Steve before, definitely. He was a substitute for Birmingham last weekend and they have their own injury problems.
‘He will be pushing hard to get into their side and was sub last week, but he is someone that we know well.
‘At the moment, we have Callum Johnson and Haji Mnoga who can cover. I always feel it’s best to play a natural full-back even if it’s on the wrong side.
‘Those are my options, one of my right-backs.’
Pring featured 15 times for Pompey before Bristol City exercised their option to recall him to cover injuries at Ashton Gate.
The Blues travel to the Robins in the FA Cup on Sunday but Pring will not be involved, having already represented Jackett’s side in the competition.
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