Pompey were held to a draw in a League One contest that was scrappy, but nonetheless contained good chances for both sides.
Daniel Kanu and Paddy Lane hit the woodwork as the game got off to a fast start, but neither team could force a winner.
With closest rivals Derby and Bolton both losing, however, it still proved to be a productive weekend for the Blues.
John Mousinho unsurprisingly stuck with the same side that inflicted a heavy defeat on Reading the previous weekend.
There was one change on the bench, however, with Gavin Whyte making way for a fit-again Myles Peart-Harris.
It was an electric start to the contest, with both sides having an opportunity to break the deadlock in quick succession.
Charlton were first up, as Kanu saw his drive rebound back off the inside of the post and into the arms of Will Norris.
The visitors got the ball straight up the pitch and Abu Kamara laid it off for Colby Bishop to force a save from Harry Isted.
And Pompey had two more excellent opportunities to take the lead in a first half that grew scrappier as it progressed.
Owen Moxon did well to control Marlon Pack’s throw before hitting a dipping volley that Isted tipped over the bar.
They went close again on 16 minutes after Joe Rafferty had lifted a cross into the box from out on the right.
Callum Lang’s initial effort was kept out by Isted at point-blank range, with Lane then heading the loose ball against the bar.
The chances began to dry up with injuries halting the momentum, although a couple of sloppy moments at the back to raise Addicks hopes.
Tennai Watson’s delivery was not dealt with, but Kanu and Alfie May were both unable to turn it home.
And when Conor Shaughnessy was dispossessed inside the area in stoppage-time, Karoy Anderson could only pick out Rafferty, who cleared the danger.
Half Time: Charlton 0 Pompey 0
It was the hosts who looked stronger immediately after the restart and Pompey had to deal with a couple of early corners.
But with a number of niggly challenges, neither side was able to find any sort of rhythm as the game became increasingly bitty.
Mousinho freshened things up with a change just past the hour mark, as Jack Sparkes came on for Connor Ogilvie.
The Blues were struggling to make the kind of attacking impact they had shown earlier in the afternoon, with moves too often breaking down in the final third.
They dealt with a corner at the other end, but the ball came back into their box and Norris came to the rescue to deny Rarmani Edmonds-Green, with Bishop on hand to do the mopping up.
Pompey then won a flag-kick of their own and Lane’s delivery was flicked narrowly past the post by Lang.
A double switch followed on 73 minutes, with Lang and Lane making way for Kusini Yengi and Peart-Harris.
With a couple more stoppages to check on hurt players – one for each side – the action was still not being allowed to properly get going.
Pompey did start to cause some problems, though, with Isted tipping a Sparkes free-kick over before Moxon’s corner ricocheted around the box.
The visitors then broke quickly and a shot from Kamara took a wicked deflection and dipped onto the roof of the net.
And when Peart-Harris was sent racing through on goal, it took a superb sliding challenge from Macaulay Gillesphey to deny him.
It was certainly an open affair as the contest entered seven minutes of stoppage-time, but the match ended goalless.
Charlton (3-1-4-2): Isted; Edmonds-Green, Jones, Thomas; Dobson (c); Watson (Gillesphey 78), Bakinson (Camará 78), Anderson (Edun 90), Small; May (Aneke 61), Kanu (Campbell 90)
Booked: Bakinson, Jones
Subs not used: Maynard-Brewer, Ladapo
Pompey (4-2-3-1): Norris; Rafferty, Raggett, Shaughnessy, Ogilvie (Sparkes 61); Moxon, Pack (c); Kamara, Lang (Yengi 73), Lane (Peart-Harris 73); Bishop
Subs not used: Macey, Towler, Martin, Saydee
Referee: Robert Madley
Attendance: 16,732 (3,155 Pompey fans)