Preston took the lead through Iain Hume who slid home after being put through by an Eddie Johnson pass. Hume has been a revelation scoring six in his last six and Preston are heavily reliant on the frontman.
Unfortunately, North End were unable to hold onto their lead with Greg Halford who denied Preston a trip to Wembley when he was at Sheff Utd, headed home from a corner for Pompey.
The Whites remain second bottom although Scunthorpe leapfrogged them as they had a sensational home win over top of the table QPR. Sheff Ut sunk to the bottom as Preston now are 7 points off safety and 9 points off Doncaster where they travel to on Tuesday evening.
With six games left Preston would need to pick up almost all of the 18 points available and even that might not be enough to see the Whites remain in the Championship although form has improved markedly under Phil Brown.