Pompey closed in on the play-offs with a hard-earned win over Bury.
Matt Clarke got the crucial goal as the Blues picked up a 1-0 win over the bottom-of-the-table side at Fratton Park.
That makes it seven wins out of eight for Kenny Jackett's men as their flying form continued in front of a crowd of 17,549.
Pompey had the vast majority of the ball and territory but found the improving Shakers hard to break down.
Danny Rose forced Leo Fasan into a fine save with his 30-yarder after 15 minutes.
Fasan again saved from Gareth Evans after 34 minutes after a fine run from Jamal Lowe.
There was applause for Pompey hall-of-famer Svetoslav Todorov at the interval, as he was introduced to the crowd along with FA Cup-winning captain Sol Campbell.
The goal came in the 62nd minute when Evans' header was met by Clarke from a corner.
From there, Pompey looked comfortable, with former striker Chris Maguire going closest for the visitors as he headed over Jay O'Shea's free-kick.
Danny Mayor also headed wide in the 84th minute, but the home side saw out the game comfortably enough.
That means goals scored now separates the Blues from the play-offs, with sixth-placed Charlton scoring two more than the Blues.