Goals from Colby Bishop – one of which was a penalty – either side of half-time secured the Blues their first win of the new League One season.
It maintains Danny Cowley’s side’s unbeaten start to the season and moves Pompey up to ninth.
Here’s how The News rated the performance as temperatures rose to 33 degrees in Gloucestershire.
13. Owen Dale - 6
(Replaced Reeco Hackett on 67 minutes): Booking was only contribution of note once introduced - but game was already won. Photo: NationalWorld
14. Ronan Curtis - 6
(Replaced Michael Jacobs on 70 minutes): Added a threat and had once decent run on goal. Photo: NationalWorld
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