Jamal Lowe has admitted Pompey need to be more ruthless in front of goal.
The Blues were held to a 1-1 draw at Accrington on Saturday – meaning their lead at the top of League One was cut to two points.
It took the visitors 62 minutes to open the scoring at the Crown Stadium as Oli Hawkins prodded home Gareth Evans’ free-kick.
John Coleman’s side were level just two minutes later, though, when Michael Ihiekwe’s towering header beat Craig MacGillivray.
Pompey had the opportunities to put the game to bed in the first half-hour, however.
Kenny Jackett’s men dominated but couldn’t find a way past Connor Ripley in the Accy net.
Man-of-the-match Lowe was the Blues' chief attacking outlet, although he had a few efforts thwarted by the Accrington keeper.
The winger feels his side start being more clinical in the final third.
Lowe said: ‘I think so, yeah (that Pompey need to be more ruthless).
‘Some of it is the luck of the bounce. Sometimes it just wasn’t bouncing to us.
‘But it is about being ruthless because we have been having a lot of possession and a lot of chances.
‘It’s just about making sure we take them.
‘There were no spectacular saves from their keeper, saves you expect him to make,
‘But sometimes they go in, so it’s just one one of those things.
‘We’ve got to make sure that we go into the next game and be more clinical.’
Pompey’s stalemate at Accrington – coupled with Peterborough’s 2-1 win at Burton – slashed their advantage at the summit of the division.
A draw against Coleman’s play-off chasers may prove to be a decent result if the Blues clinch promotion this season.
But Lowe was frustrated the Blues didn’t put their goalscoring chances away when they were at their rampant best.
He added: ‘It is a good point.
‘If you’d have said on Friday we’ll come to Accrington and get a point we’d have taken it.
‘But in the first half we could have definitely had more.
‘They sharpened up a little bit in the second half and we were going uphill, which is a major factor.
‘You can’t play dominant football for 90 minutes, every team has their spell.
‘But then again the second half was very scrappy and nobody had a spell.
‘We had our chances in the first half to put it out of sight.’