Lee Brown and Charlie Daniels are both scrapping for the role when the Blues take on Salford City in the Papa John's Trophy final today (3pm).
Brown was undisputed first choice on the left-hand side of defence when fit during the first half of the season.
However, Daniels' arrival in January to replace Cam Pring – who had his loan spell cut short by Bristol City – has made things much closer.
The experienced duo have been sharing the position since the ex-Bournemouth favourite joined on a free transfer from Shrewsbury.
Daniels has started seven games, while Brown's since featured from the outset in four.
However, there are calls from sections of fans for Jackett to settle down the role in a bid to reignite Pompey’s faltering League One promotion push.
The Blues first have their Papa John’s Trophy crown to finally defend, with the 2019-20 final taking place almost a year after it was originally scheduled amid the Covid-19 outbreak.
But who will get the nod between Brown and Daniels at the national stadium remains too close to call.
And with 13 league games remaining, it seems that’s the way it’ll stay until the end of the season.
Pompey boss Jackett said: ‘It is possible (to settle down the role). I do think, with both being senior players, a few games each they've been able to dovetail and freshen up.
‘Similarly, both players would say that they would want the shirt and if they produce, they keep the shirt.
‘Players do want that and I understand that but there are occasions when you can dovetail two experienced players as it's a heavy workload in League One at the moment.
‘Charlie has just come in and played well against Sunderland on Tuesday, particularly in the first half when he put some early crosses into the box and played some passes down the line in the second half.
‘Over a period of time, Lee has been a good left-back for Pompey. They're both good players and professionals.’
Daniels was handed a wing-back role in the 2-1 loss at promotion-rivals Doncaster earlier this month.
The former Premier League defender perhaps didn’t get forward as much as Jackett would have liked in that defeat.
However, Pompey’s manager felt Daniels gave a decent account of himself in Tuesday’s 2-0 reverse to Sunderland at Fratton Park.
Jackett added: ‘You need movement and options as well, it's never one thing.
‘Charlie has got a good left foot and got some good crosses in against Sunderland in the first half.’
A message from the Editor, Mark Waldron
On Saturday, March 13 Pompey will finally get their day at Wembley.
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