Regan Poole headed home the winning goal against his former club as Pompey beat Lincoln to remain top of the League One table.
He struck right at the end of the first half after Paddy Lane had earlier cancelled out Hakeeb Adelakun’s opener for the Imps.
The hosts were not at their best in an attacking sense, but they still dominated the majority of the Fratton contest.
John Mousinho made two changes from the side that won at Barnsley to top the table earlier in the week.
Jack Sparkes and Abu Kamara were both restored to the starting line-up, with Connor Ogilvie absent due to a groin problem and Gavin Whyte dropping to the bench.
Spirits were high as the game kicked-off in the Fratton sunshine, but the visitors soon soured the mood.
Lasse Sørensen stole possession from Sparkes on the right and found former Pompey forward Reeco Hackett.
He then played the ball to Adelakun and Conor Shaughnessy's attempted clearance ricocheted against the forward and into the net.
But the Blues were not behind for long and this time it was the Imps who were found lacking at the back, with Kamara taking advantage of a poor headed clearance.
He found Alex Robertson, who played the ball across to LANE and the winger had time to get it onto his left foot and squeeze a shot inside Lukas Jensen’s near post.
The rest of the first half followed a familiar pattern, with the home side dominating possession, but struggling to break through a stubborn back-line.
A Marlon Pack free-kick was deflected past the post, while Jensen did well to stop Colby Bishop getting on the end of a Joe Rafferty set-piece.
Their opponents, meanwhile, were certainly in no hurry and looking to use up as many minutes as referee Paul Howard would allow.
But they could not prevent Pompey from taking the lead for the first time in the contest deep into stoppage-time.
Sparkes received a pass from Kamara and swung in an excellent cross that was nodded home by POOLE at the back post.
Half Time: Pompey 2 Lincoln 1
The hosts continued to apply pressure following the restart and there were a couple of half-chances for Bishop early in the second half.
They then embarked on a quick break up the pitch that ended with Lane’s angled effort saved by Jensen and his follow-up centre diverted behind.
Pompey were on top and just looking to find the third goal that would give them a cushion and ease any nerves.
There was a chance for the skipper when Lincoln failed to clear their lines, but Pack angled his shot over the bar.
Then, a few moments later, Bishop was unable to make a clean connection when Kamara cut the ball back for him.
And when the lively Joe Morrell tried his luck with a cleanly struck effort from the edge of the box, his team-mate Kamara inadvertently got in the way.
Mousinho freshened things up with a double switch on 74 minutes, as Robertson and Kamara made way for Tino Anjorin and Whyte.
Lincoln had not been showing much attacking ambition despite trailing, but suddenly started to push forward as the game entered its closing stages.
There was a nervy moment when Will Norris was unable to hold on to a cross and the keeper recovered well to deny Jack Burroughs.
He made an even better stop right at the death, keeping out Paudie O’Connor’s header at point-blank range to ensure Pompey maintained their spot at the summit.
Pompey (4-2-3-1): Norris; Rafferty, Poole, Shaughnessy, Sparkes (Towler 90+3); Morrell (Raggett 90+3), Pack (c); Lane (Devlin 87), Robertson (Anjorin 74), Kamara (Whyte 74); Bishop
Goals: Lane 8, Poole 45+3
Booked: Robertson, Morrell, Pack
Subs not used: Schofield, Stevenson
Lincoln (3-4-3): Jensen; O’Connor (c), Jackson, Roughan (Mitchell 84); Sørensen, Hamilton, Erhahon, Burroughs (Brown 84); Bishop (Smith 75), Hackett (Makama 75), Adelakun (Duffy 75)
Goals: Adelakun 5
Booked: Hackett, Erhahon
Subs not used: Wright, Eyoma
Referee: Paul Howard
Attendance: 17,748 (475 away fans)