Pompey kept their position at the League One summit after scoring late in each half to beat in-form Bolton at Fratton Park.
The visitors had not tasted defeat for more than two months, but fell behind to Conor Shaughnessy’s glancing header.
And the Blues made sure of a deserved victory in front of the Sky Sports cameras when Kusini Yengi struck at the death.
John Mousinho made a single change from the side won on the road at Northampton nine days earlier.
Joe Morrell returned following a two-match ban and replaced Christian Saydee, with Alex Robertson moving further forward.
Backed by the soundtrack of a vociferous crowd, there was plenty of grit and determination on show in the opening stages, even if real quality was lacking slightly.
Bolton started to enjoy a few forays forward, but there was little to trouble either keeper in the opening stages.
The hosts did survive one scramble in their box, with bodies thrown in front of the ball to repel it away from Will Norris.
And the chances started to increase as the first half progressed, with one Blues move splitting their opponents open.
A pass from the lively Abu Kamara sent Yengi away and he tried to unselfishly square for Robertson, but the ball would not land for the Australian midfielder.
Wanderers were then left wondering just how they failed to break the deadlock on 28 minutes after Paris Maghoma swung in a teasing cross.
Jón Daði Böðvarsson got on the end of it and drew a fine save from Norris, but the ball ran loose for Dion Charles, who somehow screwed it wide with the goal gaping.
The hosts were soon on the attack themselves and a nice passing move ended with Nathan Baxter getting down to deal with Robertson’s low drive.
And it was then Pompey’s turn to wonder just how the had not managed to score after Kamara’s header sent Yengi racing away.
He did brilliantly to beat Ricardo Almeida Santos and get a shot away that Baxter did well to get something on.
The ball was still trickling towards the net, however, and Gethin Jones had to clear it before Kamara could bundle home.
It was only a brief respite for Bolton, however, and the goal arrived just before the break, as a corner from Jack Sparkes was glanced home by SHAUGHNESSY.
Half Time: Pompey 1 Bolton 0
The hosts looked to increase their advantage when the action restarted and they were soon causing plenty of problems.
And there was a chance when Paddy Lane drilled in a low shot that Baxter could not hold, but the keeper grabbed the loose ball before Yengi could reach it.
Mousinho was forced to make a change when Kamara picked up a knock and tried to continue before eventually being replaced by Gavin Whyte on 67 minutes.
They were still looking to attack their opponents and got into some dangerous positions, but the ball would not quite land.
Bolton were not given a moment to settle, with Pompey pressing their opponents high up the pitch and keeping the tempo high.
The visitors did have a chance to level when Böðvarsson tried to sneak a shot inside the near post that Norris managed to grab.
It began to feel tense inside Fratton Park as the seconds ticked down and Terry Devlin offered some fresh legs in place of Lane.
Yengi had a chance to wrap the points up on 88 minutes, though, glancing a header wide after meeting a Sparkes corner.
But the Australian did get the goal his tireless play deserved moments later after some great work from Whyte.
The winger swapped passes with fellow substitute Devlin and sent in a fine low pass that was gobbled up by YENGI to put any thoughts of a Wanderers comeback to bed.
Pompey (4-2-3-1): Norris; Rafferty, Raggett, Shaughnessy, Sparkes (Swanson 90+3); Morrell, Pack (c); Kamara (Whyte 67), Robertson, Lane (Devlin 82); Yengi (Saydee 90+3)
Goals: Shaughnessy 45, Yengi 88
Booked: Robertson, Sparkes, Rafferty
Subs not used: Schofield, Towler, Martin
Bolton (3-1-4-2): Baxter; Dacres-Cogley (Mendes Gomes 81), Almeida Santos (c), Toal; Sheehan; Jones, Maghoma (Dempsey 67), Thomason (Morley 67), Williams (Iredale 67); Böðvarsson, Charles (Adeboyejo 81)
Booked: Thomason, Sheehan, Mendes Gomes, Jones
Subs not used: Forrester, Jerome
Referee: Paul Howard
Attendance: 19,052 (742 away fans)