Two high-quality goals spare Portsmouth’s blushes as the 2008 FA Cup winners laboured to a 2-1 first round win at National League Harrogate.
Brandon Haunstrup and Ronan Curtis produced an excellent strike each as Pompey came back after Mark Beck had given Town a deserved early lead.
Portsmouth, who are in the bottom half of League One after an indifferent start to the season, will host non-league Altrincham in round two.
A power cut at the CNG Stadium prevented supporters from entering the ground before the scheduled 7.45pm kick-off time, with the match eventually getting under way almost an hour later.
Harrogate took the lead after seven minutes when George Smith’s long free-kick into the box caused chaos in the Pompey defence, with Beck heading in at the back post.
The hosts enjoyed the better of the opening stages but Portsmouth equalised against the run of play after 17 minutes. Makeshift right-back Haunstrup cut inside onto his stronger left foot and curled a 20-yard effort inside the far post.
Connor Hall headed wide and Jack Muldoon had a powerful effort blocked as Harrogate responded positively to conceding.
Pompey captain Tom Naylor had to be replaced by Anton Walkes after picking up an injury and the visitors had a let-off when Muldoon raced clear after an error by Christian Burgess, only to smash his effort narrowly wide.
A neat Portsmouth move led to Ben Close testing James Belshaw from 30 yards but although the keeper spilled, the loose ball fell to a defender and Harrogate cleared their lines.
The North Yorkshire side replaced Warren Burrell with Jack Emmett after 32 minutes, while Portsmouth’s Sean Raggett made way for Paul Downing as a spate of injuries disrupted the flow of the contest.
Curtis put the away side in front four minutes before half-time when he collected John Marquis’ pass and fired a stunning half-volley past Belshaw from 30 yards.
Marquis and Ryan Williams both struck efforts from distance wide after the break, with Australia international Williams later cutting infield and testing Belshaw with a curling effort.
A Gareth Evans corner caused panic in the Harrogate defence, but Marquis was unable to force his initial header or a follow-up effort into the net.
Substitute George Thomson rifled Harrogate’s first meaningful effort of the second half a fraction wide after 65 minutes, with goalkeeper Craig MacGillivray rooted to the spot.
Beck headed a Smith corner straight at former Town player MacGillivray, while at the other end Evans struck a 20-yard effort wide.
Hall headed over from a corner as Harrogate enjoyed a sustained spell of pressure, but they were almost caught on the counter when Lee Brown fizzed an effort across the face of goal.
Muldoon hit a late effort straight at MacGillivray after bursting into the box but the non-league outfit were unable to secure a replay.