Pompey crashed to a miserable 1-0 home defeat to Torquay after turning in arguably their worst home display of the season.
Billy Bodin struck the only goal of the game just before the half-hour mark to cap a woeful first 45 minutes from the Blues as they failed to muster a shot on goal of any real note.
While the Blues improved marginally after the break, it was only in the last 10 minutes or so that the home side showed anything like the kind of urgency required in trying to find a way back into the game.
And even then they failed to create anything like enough quality in the final third and struggled to get any kind of cohesive play going.
Chances were at a premium but substitute Wes Fogden might have snatched a dramatic late point, only to blaze over the crossbar when well placed.
But boos rang out at the final whistle as Pompey saw themselves dragged back into serious relegation trouble as their dreadful form at Fratton Park continued with a seventh League Two loss on home turf of the campaign.