A single header from Christian Burgess was enough for Portsmouth to beat Leyton Orient for the first time since 1976 and end a run of consecutive defeats.
The scoreline should have been more comfortable, in truth, as Pompey squandered numerous opportunities to score and referee Chris Sarginson and his assistants failed to give key decisions in Pompey's favour.
The first of those came when Conor Chaplin instinctively hooked Enda Stevens' cross past Alex Cisak and into the corner of the net only for the linesman to cut short the celebrations by raising his flag for offside. The goal didn't look anywhere near offside from the stands and the replays confirmed that suspicion.
Then there were two penalty appeals for the visitors that were denied by the referee. It would have been fortunate to give a spot kick for handball on Gareth Evans' cross into the box but Kyle Bennett looked to have been clearly tripped by the trailing leg of Chris Massey only to be booked for diving instead.
The fact that Orient fans behind the goal stated after the game that they also believed Sarginson was going to point to the spot simply backs up the belief that the referee was fairly clueless during the match.
The home fans would also highlight a penalty appeal of their own sandwiched between Pompey's claims for a spot kick. Again, it would have been harsh for Burgess to be penalised for handball during a scramble in the box but it seemed like he took Yvan Erichot clean out immediately after and that could have easily been a penalty.
Amongst all that, Amine Linganzi, starting in place ahead of Danny Rose, missed a free header. Gary Roberts failed to take full advantage when a poor Cisak clearance landed at his feet as he decided to square to Chaplin who had his shot saved rather than shoot the ball into an unguarded net instead.
Bennett and Chaplin went close again before the break as everyone at Brisbane Road wondered just how the scores were level at the break.
The second half was just as open but Pompey did far more of the attacking than their hosts. In fact, the only real danger David Forde faced was when Alan Dunne attempted to chip him from distance but the goalkeeper leapt high enough to claim.
Chaplin had a great chance to score early on but slipped just as Stevens teed him up but Orient's brittle back four always looked susceptible to conceding and that finally happened in unlikely fashion by Portsmouth standards as Burgess headed in Carl Barker's corner.
There were other opportunities to extend the score but the lack of a final ball and some crucial blocks denied Pompey the goals their play deserved.
Nicky Hunt almost scored a comical late own goal when he headed Baker's delivery against his own goalpost but one goal turned out to be enough in the end as Paul Cook's men did a professional job in seeing the game out.
Personally, it was a good feeling to finally taste victory over the side that is responsible for arguably the worst result in Portsmouth's modern history, especially as the omens seemed to be against Pompey heading into yesterday's match.
Whilst the ghost of 2002 will never be completely banished, it was great to see Pompey win this game despite getting nothing from the match officials. For a while it seemed like Orient's curse would continue.
It was an accomplished performance on the road and a far cry from the dismal defensive displays in Lancashire this season. Having said that, Pompey won't have played a team as blunt as Leyton Orient so far this season and there's no wonder that they have failed to score in so many home games judging by this match.
Still, Pompey could and should have had more and so they still have work to do going forward when playing away from home. But it was refreshing to see a solid defensive performance where the back four looked far more organised and protected by Doyle and Linganzi, with the latter impressing in particular.
The result sets up an enticing showdown with Plymouth at Home Park next week. Revenge may be on the agenda but it's a hugely important game where a defeat would already see Pompey all-but out of the League Two title race.
Yesterday's result will give everyone hope that this team have now got what it takes to avenge that play-off semi-final heartbreak and make a massive statement about their title ambitions this season.
Pompey Player Ratings
David Forde: 6 - Little to do.
Gareth Evans: 7 - Did a very professional job.
Christian Burgess: 8 - Scored the important goal and won everything in the air.
Matt Clarke: 7 - Getting back to his best.
Enda Stevens: 8 - Best performance of the season so far, both defensively and going forward.
Michael Doyle: 6 - Solid but still seems a bit off the pace.
Amine Linganzi: 7 - May have missed a sitter but looks comfortable with the ball at his feet and has plenty of "bite" to his game, too.
Gary Roberts: 6 - Had his moments but should have done better.
Carl Baker: 7 - Influential in the second half.
Kyle Bennett: 7 - Always caused problems for the Orient defence.
Conor Chaplin: 7 - Wrongly denied what would have been another outstanding goal for his collection.
Substitutes
Liam O'Brien
Tom Davies
Danny Rose (Linganzi 67): 6 - Slotted in fine.
Kal Naismith
Milan Lalkovic (Bennett 82): N/A - Still looks like he has something extra about him.
Curtis Main (Chaplin 67): 6 - Worked hard but lacks any real pace.
Michael Smith