Pompey’s Emirates FA Cup adventure came to an end with a narrow third round defeat at Tottenham Hotspur.
But it took a moment of quality from England skipper Harry Kane early in the second half to secure the Premier League side’s progress.
The Blues had earlier threatened to cause an upset, with Reeco Hackett’s fine effort well saved by Fraser Forster.
Interim head coach Simon Bassey made four changes from the side beaten by Charlton in the league on New Year’s Day.
Leading marksman Colby Bishop returned to the starting line-up, while there were also spaces for Hackett, Ryan Tunnicliffe and Denver Hume.
Joe Pigott and Ronan Curtis both dropped to the bench, with Marlon Pack suspended and Dane Scarlett unable to feature against his parent club.
There was a welcome sight on the bench, as Louis Thompson took his place after recovering from the broken leg suffered back in August.
It was not clear that there were two divisions separating the teams when the action began, as Pompey more than held their own.
They made their intentions clear with a dangerous earlier delivery from Connor Ogilvie that had to be headed behind by Kane.
And the visitors almost took the lead on 12 minutes, when Bishop nodded the ball down for Hackett in the box.
He hit an acrobatic effort that was heading for the bottom corner, but Forster got down to his right to make the save.
There was little happening at the other end of the pitch, despite Tottenham winning a host of corners.
They were all taken by Heung-Min Son and each of them were dealt with by either Josh Griffiths or one of his defenders.
Spurs did have an opportunity late in the half when Joe Morrell was penalised for a foul on Son 25 yards out.
The free-kick from Kane flew straight into the wall, but the loose ball was sent into the box by Ryan Sessegnon and headed over by Davinson Sanchez.
Half Time: Tottenham 0 Pompey 0
The home side unsurprisingly emerged stronger after the interval and came close to breaking the deadlock on 49 minutes.
Emerson Royal got on the end of Son’s cross and his header bounced back off the inside of the post, narrowly avoiding hitting Sean Raggett before being gratefully gathered by Griffiths.
It was only the briefest of reprieves for the Blues, however, as they did fall behind just a few moments later.
Kane swapped passes with Sessegnon on the edge of the box and hit a fierce strike that left Griffiths with no chance.
Pompey looked for a route back into the contest, but were struggling to make any inroads in the final third.
And they might have fallen further behind on 68 minutes, with Oliver Skipp firing over from close-range after being teed-up by Bryan Gil.
The Blues then embarked on a neat passing move up the pitch, but it ended with Owen Dale seeing his shot blocked.
Bassey made a double switch on 75 minutes and there was a particularly loud welcome for Thompson, who came on alongside Josh Koroma for Tunnicliffe and Hackett.
The midfielder immediately made his presence felt with a meaty challenge on Gil that earned a yellow card.
More Pompey changes followed late on, as Pigott and Michael Jacobs replaced Bishop and Morrell, while Dale then made way for Curtis.
And although they were unable to find a late leveller to secure a replay, the Blues could be proud of their efforts.
Tottenham (3-4-2-1): Forster; Tanganga, Sanchez, Davies; Royal, Sarr, Skipp, Sessegnon (Spence 77); Gil (Devine 90+2), Son; Kane (c)
Goals: Kane 50
Booked: Sanchez
Subs not used: Lloris, Doherty, Romero, Lenglet, Højbjerg, White, Mundle
Pompey (3-5-2): Griffiths; Morrison, Raggett (c), Ogilvie; Swanson, Tunnicliffe (Thompson 75), Morrell (Jacobs 85), Hackett (Koroma 75), Hume; Bishop (Pigott 85), Dale (Curtis 87)
Booked: Thompson
Subs not used: Oluwayemi, Freeman, Dockerill, Payce
Referee: Thomas Bramall
Attendance: 60,161 (8,880 Pompey fans)