Ben Thompson has been told to keep finding the back of the net after finally getting his first Pompey goal.
The Millwall loanee got the opener as the Blues beat National League Maidenhead United in the FA Cup.
That represented the first time the 23-year-old had netted for Pompey on his 16th appearance for the club.
Thompson has been employed in deep and attacking midfield roles this season, earning rave reviews from supporters.
But one area the midfielder has been told to improve is his goalscoring record.
Remarkably of the five goals Thompson has scored in his early career, four of those have come in the FA Cup.
Now Jackett is hoping the midfielder’s latest strike in English football’s oldest cup competition can spark a fine run in front of goal for him.
He said: ‘I've been pleased with what Ben has brought in his time here.
'But there are times where he should be scoring goals as well.
'He has the energy to be able to do that.
'I'm pleased he's got his first goal for the club and it was a key goal as well.
‘He's got up to speed pretty quickly for a loan player that had not played too much football when he came in.
'I've told him that there will have to be times where he does get forward from midfield and score.
'Because Ben (Thompson) has a good, general all-round game.’
Jackett did not underestimate the importance on Thompson’s first Blues goal, either.
Fellow midfielder Tom Naylor hit the crossbar from close range after 22 minutes in the FA Cup encounter at Magpies.
The one scare Pompey did have then came three minutes later.
Ayo Obileye superbly took a pass in his stride, then unleashed an effort which came back out off the post.
It looked as though it would be all square at the break, only for Thompson to pop up with his first Pompey goal.
And Jackett believes that set Blues on their way to what proved an easy triumph in the end.
‘It was a key one the first one,’ added Jackett
'Maidenhead going down the slope were going to be quite strong, whatever half that came you have to combat that and come through to be able to win the game.
'Ben's finish from a left-wing cross was a key one for us, promoting and setting up a dominant second half for us.
‘We did what we needed to do in the second half.
‘We needed to go away from the opposition, if we could.
'I was pleased seeing the second, third and fourth goals going in, it got more comfortable.
'It turned into a very professional job for Portsmouth.'