Pompey’s January blues continued as they slipped to a narrow League One defeat at high-flying Sunderland.
They dominated the first half, without really looking likely to break the deadlock and were caught by some sloppy defensive play.
Elliot Embleton took advantage to net the game’s only goal before the interval, with the Black Cats comfortably holding onto their lead.
Danny Cowley made three changes from the side that were held to a draw at AFC Wimbledon earlier in the week.
Skipper Clark Robertson returned for his first league start since mid-September, while there were also spots for Reeco Hackett and Ronan Curtis.
Connor Ogilvie dropped to the bench after missing training with a nose injury and was joined by Lee Brown and George Hirst.
It was a familiar tale for Pompey when the action started, as they dominated possession, but could not capitalise on that in the final third.
Tyler Walker saw an effort blocked inside the box, while a decent Hackett delivery was headed to safety.
The best opportunity came when Hackett’s corner was flicked on by Curtis, with Lynden Gooch having to hack clear before Walker could pounce.
But the Black Cats almost broke the deadlock with their first attack after a loose pass from Curtis was intercepted.
Embleton advanced forward and bent in a shot that was pushed clear by a diving Gavin Bazunu, with the keeper recovering to beat the same player to the loose ball.
Sean Raggett saw an angled attempt blocked, while a misunderstanding between Thorben Hoffmann and Danny Batth resulted in a Blues corner, but half-chances were the order of the day.
There was a let-off at the other end when Raggett was dispossessed by Leon Dajuku, who could not find the target from out wide.
But there was no reprieve on 40 minutes, as this time it was Hayden Carter who had the ball stolen from him.
Embleton played the role of pickpocket and he slotted past Bazunu to open the scoring following a neat one-two with Ross Stewart.
Pompey tried to hit back just before the break, but Marcus Harness could only hook Curtis’ cross over the bar.
Half Time: Sunderland 1 Pompey 0
The visitors did not enjoy as much control when the match restarted and were looking sloppy on the ball.
There was not too much happening at either end of the pitch, with Corry Evans and Dan Neil both firing wide for Sunderland.
Pompey started to find a bit more rhythm as the second half progressed, but Hoffmann was still having a quiet afternoon.
Cowley made a double switch on 71 minutes, as Curtis and Louis Thompson were replaced by Hirst and Shaun Williams.
However, the hosts were still finding it all too comfortable to keep their opponents at bay, as the Blues’ frustrations continued.
Robertson made way for Michael Jacobs as Cowley made an attacking last throw of the dice for the closing stages.
And the newcomer made an instant impact, bursting through the Black Cats back-line, only to be halted just before he could attempt to test Hoffmann.
Jacobs again found space to advance towards goal soon after, but his 20-yard effort flew straight at Hoffmann.
And he whipped in a teasing corner on 90 minutes, with a firm header from Hirst flying narrowly over the bar.
But that was as good as it got for the visitors, who had to make the long trip home on the back of a defeat.
Sunderland (3-4-1-2): Hoffmann; Flanagan, Batth, Doyle; Gooch, Evans (c), Neil, Cirkin; Embleton (Winchester 83); Dajaku (O’Brien 88), Stewart
Goals: Embleton 40
Subs not used: Patterson, Hume, Xhemajli, Diamond, Kimpioka
Pompey (3-4-1-2): Bazunu; Carter, Raggett, Robertson (c) (Jacobs 78); Romeo, Thompson (Williams 71), Morrell, Hackett; Harness; Walker, Curtis (Hirst 71)
Booked: Romeo, Williams
Subs not used: Steward, Freeman, Ogilvie, Brown
Referee: David Rock
Attendance: 32,220 (1,434 Pompey fans)