Trailing at half-time to Yuki Ohashi’s opener, John Mousinho’s men levelled on 62 minutes through Callum Lang’s first of the season, finishing off Josh Murphy’s cross.
Then, 11 minutes from time, Conor Chaplin’s right-wing corner was headed home by Bowat to secure a 2-1 triumph.
It was a priceless win for the Blues, lifting them into 21st - a point outside the relegation zone - and here are our player ratings…
5. Ibane Bowat - 8 - MOM
Unlikely match hero. Definitely improving with a run of games after his long injury lay-off, becoming more comfortable in his surroundings. More composed by the match, his 79th-minute header from Chaplin’s corner earned the points. Photo: Simon Roe
6. Zak Swanson - 8
Absolute livewire. Playing out of position at left-back, yet still as committed as ever. Scrapped away, defensively sound and always keen to push forward, with his shot earning Pompey the corner from which Bowat scored, Photo: Simon Roe
7. John Swift - 5
(Replaced by Mark Kosznovszky on 57 mins) Poor pass in the Blackburn half, allowed the opposition to counter and break the deadlock on 36 minutes. It was a dreadful mistake, changing the complexion of the game. From that point, Swift had lost the faith of the fans. Photo: Graham Hunt
8. Andre Dozzell - 7
Unsurprisingly restored to the team in place of the suspended Pack after serving his own one-match ban and gave Blues mobility and work-rate in the centre of midfield. Doesn’t always catch the eye, but a vital cog. Photo: Graham Hunt