Jack Diamond’s 94th-minute effort sealed the win for the League Two side, after Luke Armstrong’s 44th-minute opener for the visitors was cancelled out by Ellis Harrison (45+2).
The defeat sees Pompey’s six-match winning run end and the Blues absent from Monday night’s third-round draw…
Here’s how our chief sports writer rated the players’ individual performances...
9. Marcus Harness - 6
Bright in the first half but went quiet when pushed wide late on in system changes. Photo: The News
10. Michael Jacobs - 5
Caught get going and, other than odd decent run, failed to conjure up creativity. Photo: The News
11. Ellis Harrison - 7
(Replaced by Ronan Curtis on 60 minutes): Marked a start with a smart finish, yet inevitably was rusty. Photo: JPIMedia
12. Lee Brown - 6
(Replaced Kieron Freeman on 57 minutes): Came on in system change, but couldn’t fire up the Blues. Photo: JPIMedia