Pompey's future remains in some doubt, despite positive noises from the representaties of former owner Sacha Gaydamak but, despite Nick Barmby heading home for Hull with just under half an hour left, they continue their march up the table after goals either side of half-time from David Nugent and Greg Halford.
The south coast club last night claimed they were on the brink of ceasing trading, a scenario that now seem to have been avoided, but Steve Cotterill's players remained focus on their duties, heaping more misery on Hull manager Nigel Pearson in the process.
Hull have taken only two points from their last five games and continue their slide towards the bottom three with a quarter of the season gone.
Player/coach Barmby, Nolberto Solano, Rowan Vine and Jamie Devitt all returned to Hull's starting line-up, while Aaron Mokoena was Portsmouth's only change.
Robert Koren's early shot and Barmby's header soon after were both held by Portsmouth goalkeeper Jamie Ashdown and at the other end John Utaka's drilled shot was caught by Hull goalkeeper Matt Duke.
Pompey enjoyed the lion's share of possession midway through the first period and were almost rewarded in the 27th minute when Nugent's 25-yard shot crashed back off the crossbar.
A minute later Nugent headed just wide from Liam Lawrence's corner, but although Devitt went close for Hull with a carbon-copy effort from Vine's cross, the visitors broke the deadlock on the stroke of half-time.
Utaka's header was parried by Duke, but the Pompey forward's fine pass moments later picked out Nugent in space and he ran on into the penalty area to plant a right-footed shot into the bottom corner.
Pompey doubled their lead two minutes after the restart. Hull defender Daniel Ayala was adjudged to have fouled Dave Kitson and Halford arrowed the subsequent free-kick into the bottom corner from 20 yards for his first competitive goal since April 2009.
Nugent, twice, and Utaka squandered further goalscoring chances before Hull lifted themselves and deservedly reduced the arrears in the 62nd minute through Barmby, who expertly headed home Koren's cross from the left into the top corner.
Vine's 20-yard shot was well held by Ashdown as the Tigers pressed for an equaliser, while Ayala and Kitson traded efforts from outside the area that both flew wide.
Hayden Mullins then rifled a shot from outside the area past Duke's right-hand post and Hull substitute Jay Simpson saw his 25-yard drive held by Ashdown, but the visitors closed out over four minutes of time added on without further scares to notch 16 points from the last 18 available.