Pompey celebrated victory at Cambridge today, despite playing the final 30 minutes at the Abbey Stadium with 10 men.
Amine Linganzi was shown a straight red card on 60 minutes after a two-footed challenge on Conor Newton.
But the home side were unable to make their numerical advantage count as Conor Chaplin proved the match-winner for the Blues with his fifth goal of the season.
The striker scored the only goal of the game on 24 minutes, with a beautiful header the perfect way to reward Christian Burgess’ perfectly-executed through ball from inside the U’s half.
Cambridge began the game well, but although former Pompey player Adam McGurk and Max Clarke registered efforts on goal, there was little to worry goalkeeper David Forde.
The Blues picked up the pace after a fluffed effort from skipper Michael Doyle on the edge of the box in the 17th minute.
And their reward was a magnificent headed effort from Chaplin in the 24th minute that gave U’s shot-stopper Will Norris no chance.
A superbly-delivered ball from Burgess picked out the diminutive front man, who rose highest in the box to guide the ball beyond the reach of the keeper.
Cambridge responded with a strong run from Uche Ikpeazu into the Pompey penalty area.
He went down under close attention from Burgess, but the referee waved play on, despite home protests.
The Blues continued to control the rest of the first period, with Kyle Bennett firing straight at Norris.
But they were unable to add to their first-half lead as Paul Cook’s side went into the interval 1-0 up.
Pompey continued to look the most potent side going forward at the start of the second period, with Chaplin fizzing an effort wide from the angle on 49 minutes.
But Ben Williamson nearly punished some slack Blues defending when he prodded the ball just wide when it dropped to him in the box on 55 minutes.
The home side were given a major boost on the hour mark when Linganzi’s two-footed challenge on Cambridge substitute Newton saw referee Ross Joyce produce a red card.
That prompted Cook to make two immediate substitutions, with Bennett and Chaplin making way for Danny Rose and Noel Hunt.
It also initiated some Cambrige pressure, with James Dunne twice trying his luck from long range.
But despite putting the visitors under huge pressure as the clock ticked down, there were no clear-cut chances to suggest an equaliser was coming.
And despite five minutes of time added on after 90 minutes, Pompey’s defensive might was rewarded as Cook’s side picked up three valuable points on the road.