Notts County carried out a smash and grab to flatten Pompey at Fratton Park.
A goal in each half from Adam Campbell gave the Magpies a 2-1 win on a frustrating afternoon for the Blues
John Sheridan’s side were reduced to 10 men with 13 minutes left after Aaron Collins saw red.
But Paul Cook’s men, who were left fuming over what they saw as a foul on Tom Davies in the build-up to Notts County’s second, couldn’t find the leveller.
Pompey were dominant and bright in the first half but appeared to run out of ideas and looked increasingly ragged as they chased the game.
And there were boos on the final whistle as the home crowded made their feelings clear.
The pattern was set early on as wave after wave of Pompey attacks piled forward.
But the Notts County rearguard action was firm in the face of the Blues pressure.
Conor Chaplin somehow fired wide after six minutes from just a couple of yards after Enda Stevens’ cross.
And there was another big miss from the teenage hitman seven minutes later when he was clean through after a slip from Haydn Hollis. Chaplin’s shot was a weak one though, and Adam Collin easily saved.
Pompey were then undone by a rare Notts County attack after 21 minutes, as Adam Campbell was given time and space to fire home on the turn from the edge of the box.
The reply came six minutes later though with Chaplin bagging at the third time of asking.
It was decent play from first Kyle Bennett and then Gary Roberts, who reached the byline and cut back for the Academy graduate to finish from six yards.
There was a great chance for Bennett to put Pompey in front six minutes after the restart, but he put his free header wide from six yards.
Cook’s side were struggling to find the fluency of the first half, though, with the atmosphere increasingly flat.
Pompey were running out of ideas and were then caught by a sucker punch in the 71st minute as Campbell got his second.
There appeared a clear nudge on Burgess in the build-up before he finished from six yards, but the ref allowed the goal to stand.
Pompey were given hope when the Magpies were reduced to 10 men with 13 minutes left after Collins flew in late on David Forde.
Burgess was then thrown up front as Pompey tried everything to rescue the game.
The fourth official indicated six minutes of stoppage time as the Blues pushed for the leveller.
Baker’s shot from six yards was turned over by Adam Collin and then Gary Roberts drilled a 20 yarder wide at the death.
But there was no late leveller as Pompey remained fifth in the table - 11 points off leaders Plymouth.