John Marquis was on target as Pompey returned to winning ways against a spirited Lincoln side at Fratton Park.
There were chances at both ends before the break and Marquis scrambled the ball home to end his barren spell.
It was a more turgid affair in the second half, but Craig MacGillivray was not overly troubled as the Blues saw the game out.
Kenny Jackett made one change from the side that were unlucky to lose at AFC Wimbledon on Saturday.
It came at right-back where James Bolton dropped to the bench to make way for on-loan Rangers youngster Ross McCrorie.
There was a familiar face in the starting line-up for the Imps – now managed by former Fratton boss Michael Appleton – as striker John Akinde led the line.
Pompey continued the theme of recent weeks by dominating possession throughout the first half, although the visitors had arguably the better chances.
There were half-chances for Ryan Williams and Marquis, but Lincoln really should have broken the deadlock on seven minutes.
Michael O’Connor’s free-kick found Callum Connolly totally unmarked in the box, but the defender headed wastefully wide.
He rescued his side at the other end soon after, though, with a key interception to stop Marquis meeting Williams’ cut-back from a neat Ben Close pass.
MacGillivray was then called into action to keep the game goalless, getting down to his left to save a fierce long-range effort from the lively Bruno Andrade.
It looked like being a brief reprieve, however, as the resulting corner saw the ball ping around the Blues box, but twice stopped from crossing the line by the Scottish keeper.
Marquis then fired over from a tight angle as the hosts continued to see plenty of the ball, while Sean Raggett – facing his former club – saw a header deflected into the arms of Josh Vickers.
But the Lincoln keeper was beaten on 28 minutes, despite making a decent stop to keep out Christian Burgess’ bullet header.
The ball ran loose, though, and MARQUIS had the simple job of nudging it over the line from just a yard out.
Andrade was still proving a menace at the opposite end of the pitch and a teasing cross somehow evaded everyone in the box, while a crunching Tom Naylor challenge halted his run down the left.
There was one more chance for Lincoln to level before the break, although MacGillivray was not too bothered by Andrade’s firmly-struck effort from outside the box.
Lincoln City 0
Raggett collected the first booking of the evening shortly after the restart following a late challenge on Tyler Walker.
But referee Tom Nield somehow failed to spot the defender getting his shirt clearly tugged as he tried to meet a free-kick moments later.
Williams then had a chance to double the hosts’ lead following good work from Marquis and Marcus Harness, but was unable to find the target with a fierce finish.
Lincoln had a chance to equalise following a quick break on 54 minutes, but again nobody could get the finishing touch on his dangerous delivery and Lee Brown swept up.
The game became more scrappy as the second half progressed, with the hosts struggling to keep possession as well as they had before the break.
But they almost strengthened their lead just past the hour mark, as Vickers only just managed to prevent a firm Burgess header from crossing the line.
Jackett made his first substitution on 67 minutes, with Ronan Curtis replacing Harness wide on the left.
The new man was soon involved in the action and crossed for McCrorie, who took a touch before blazing over the bar.
Gareth Evans then did well to win a corner that he took himself and although Vickers flapped at it, he got enough on the ball to get it safe.
It was as committed a display as ever from Naylor and after losing possession in a dangerous area, the skipper did brilliantly to win it back again.
A quick break offered the chance to relive some growing pressure, but McCrorie’s pass to Marquis was not quite right and the striker did well to get the ball under control before firing over.
And Evans was also unable to keep his shot down after Naylor’s cross from the right had been only partially cleared.
It had been a strange display from the referee and when a late challenge on Williams went unpunished, even the normally placid Jackett was left raging on the sidelines.
But it did not prove costly for Pompey, who saw out the four minutes of stoppage-time to claim a welcome three points.
Pompey (4-2-3-1): MacGillivray; McCrorie, Burgess, Raggett, Brown; Naylor (c), Close; Williams, Evans, Harness (Curtis 67); Marquis
Goals: Marquis 28
Booked: Raggett, Burgess
Subs not used: Bass, Bolton, Downing, Haunstrup, Cannon, Harrison
Lincoln (4-4-2): Vickers; Eardley, Connolly, Shackell (c), Toffolo; Andrade (Hesketh 85), O’Connor (Grant 80), Morrell, Payne; Akinde (Anderson 76), Walker
Subs not used: Smith, Melbourne, Lewis, Chapman
Referee: Tom Nield
Attendance: 17,266 (753 away fans)