Pompey continued their run of fine form with a 2-0 victory at a Lincoln side who had been in imperious home form.
Ronan Curtis curled home a free-kick in the last piece of action of an otherwise lacklustre opening half.
And the Imps never really did enough to threaten that lead, with John Marquis wrapping things up from the spot after Neal Eardley had fouled Steve Seddon.
Kenny Jackett stuck with the same side that knocked Barnsley out of the FA Cup on home soil at the weekend.
Cameron McGeehan was ineligible for that game, but returned on the bench and was joined by the fit-again duo of Lee Brown and Ross McCrorie.
The hosts had an early opportunity when Jorge Grant’s cross drifted towards goal and landed on the roof of the net.
But the opening 45 minutes was a largely soporific affair, with neither side able to find any kind of fluidity and possession constantly changing hands.
A quick Lincoln break might have caused a few flutters in the away end of the ground, but Tyreece John-Jules settled any nerves by blazing high over the crossbar.
Pompey had periods of possession, although were lacking penetration in the final third as the contest continued to drift along.
There was pained expressions among every man in the crowd on 30 minutes after Andy Cannon’s shot hit a defender and ricocheted back into his nether regions.
The midfielder was then involved in a neat bit of build-up play involving Ryan Williams and Ben Close, with the latter’s ball glanced wide by Marquis, who had also strayed offside.
It appeared as though the interval would arrive without any meaningful incident, but the Blues suddenly picked up in stoppage-time.
Curtis fired one effort over, while Cian Bolger did well to stop James Bolton’s low delivery reaching Marquis in the box.
A fierce volley from Cannon was then blocked before, with time almost up, Seddon was bundled over just outside the box.
Close stood over the ball and Seddon feigned to take it, seemingly confusing Imps keeper Josh Vickers as CURTIS curled past his desperate grasp.
Half Time: Lincoln 0 Pompey 1
A long-range attempt from Cannon flew not too far over the bar once the action resumed, as the Blues tried to find a cushion.
But the hosts should have been level soon after, as Tom Hopper beat former Imps defender Sean Raggett and cut back for an unmarked John-Jules to fire wastefully over.
There was still a lack of quality on show, but there was certainly more action than had been on offer prior to the break.
Curtis fizzed a low free-kick into the box and the ball bounced dangerously around before being cleared behind.
The Imps then embarked on a patient passing move up the pitch that ended with Raggett making a crunching – but fair – challenge on Tyler Walker inside the box.
A Grant free-kick was soon partially headed clear, although Conor Coventry’s follow-up was again off target.
Pompey broke quickly to carve out an opportunity of their own on 73 minutes, with Seddon having of acres of space to run into before seeing his low drive beaten away by Vickers.
Jackett made his first substitution moments later, with Cannon making way for McGeehan in the centre.
Raggett then appeared to hurt himself after sticking a foot in to block Walker’s shot, but the centre-back was able to continue after some treatment on the pitch.
Pompey were trying to wrap the match up and when a Curtis corner was only partially cleared, McGeehan curled the loose ball over.
And they had the opportunity to do just that when Seddon’s charge into the box was clumsily halted by Eardley.
Referee Ben Toner had a simple decision to make and immediately pointed to the spot, although spared the Imps defender a second booking.
MARQUIS stepped up to take the penalty and precisely squeezed the ball just inside the post to double the lead in front of the large – and noisy – travelling army.
Curtis might have added some icing to the cake late on, but Vickers made a smart stop to limit the damage for Lincoln.
Lincoln (4-4-2): Vickers; Eardley, Bolger, Shackell (c), Melbourne; Anderson (Walker 60), Morrell, Coventry (Hesketh 74), Grant; Hopper, John-Jules
Booked: Eardley, Grant, Morrell
Subs not used: Smith, Lewis, Edun, Chapman, Elbouzedi
Pompey (4-2-3-1): Bass; Bolton, Burgess, Raggett, Seddon; Naylor (c), Close; Williams, Cannon (McGeehan 76), Curtis; Marquis
Goals: Curtis 45+5, Marquis 87 (pen)
Booked: Close, Marquis, Naylor, Curtis
Subs not used: MacGillivray, McCrorie, Whatmough, Brown, Harness, Harrison
Referee: Ben Toner
Attendance: 8,983 (1,154 Pompey fans)