Adrian Segecic’s double mistake gifted Hull a narrow victory at Fratton Park.
The away-day specialists had been restricted to just one shot until the 73rd minute, such was the dominance of John Mousinho’s men.
Then Segecic was caught in possession to allow John Lundstram into the box and, when he made amends, produced a short backpass to put Nicolas Schmid in all sorts of trouble.
When Oli McBurnie slid in to challenge the keeper, the ball fell to Matt Crooks to finish into the empty net and secure a 1-0 victory.
Like Sheffield United, it was more agony for the Blues, who had plenty of the ball, a large number of corners and vastly more shots than the visitors.
Here are our Pompey player ratings…
5. Connor Ogilvie - 7
Superb in the air against the threat of McBurnie and produced a few driving runs from the back into the heart of Hull territory. Defensively sound once again. Photo: Steve Bailey
6. Zak Swanson - 7
(Replaced by Conor Chaplin on 82 mins) - Had a third-minute shot from outside the box pushed around the post by Pandur. Loves to drive inside from the left and was especially effective in the first half. Another strong showing. Photo: Simon Roe
7. Marlon Pack - 7
Helped Pompey dominate possession against Hull with excellent, yet intelligent, use of the ball throughout. Such a clever player and still has a huge role to play for the Blues. Photo: Graham Hunt
8. Ebou Adams - 7
(Replaced by Jacob Brown on 82 mins) Another powerhouse performance from a player who was absolutely everywhere and has rapidly established himself as a pivotal player for the Blues. | Graham Hunt/ProSportsImages