Alan McLoughlin challenged Dan Butler to carry his form forward after a searing display against Morecambe.
And the Pompey coach tasked the left-back with strengthening his defensive skills to give him a more complete game.
Butler, 20, was outstanding in Saturday’s 3-0 win over Morecambe – delivering an electric performance on his first start in a month.
McLoughlin lauded that effort but stated he has work to do moving ahead.
He said: ‘Dan was excellent in my opinion.
‘We went with a little less experience on the left but they stepped up.
‘Dan is great at bombing on. But as well as bombing on he has to be a great defender if he is to progress in the game.
‘If he is to get to a high level that’s what he has to do.
‘His attitude is brilliant. Spot on.
‘But you have to be a good defender, first and foremost, to be a good left-back.
‘Then the attributes he shows going forward come into play.
‘With listening, concentration and taking things on board, that side of his game has developed.
‘But one good game is nothing if it’s not carried forward.’
McLoughlin also highlighted the influence of Marcus Bean in midfield on his Pompey debut.
He said: ‘He’s solid and knows the game.
‘He knows where to stand and where to nick things.
‘He knows where to be and that’s what we’ve looked for since James Dunne got injured.
‘Maybe we lost a bit of game knowhow since Dunney got injured. That’s the reason he came in.
‘He should be delighted.’