Sean Raggett gave the Blues a 19th-minute lead, before Alex Gorrin levelled things from the penalty spot on 69 minutes.
Pompey remain fourth in the table, but have been overtaken by Lincoln, who were 1-0 winners at Swindon.
5. Lee Brown - 7
Rock solid and once again gave know how and experience to proceedings. Photo: JPIMedia
6. Marcus Harness - 7
(replaced by Ryan Williams on 82 minutes): Had some good moments amid excellent work-rate. Photo: JPIMedia
7. Tom Naylor - 8
No goal tonight but still in magnificent form for Blues. Photo: JPIMedia
8. Andy Cannon - 7
(replaced by Bryn Morris on 79 minutes): Developing into such a key player, so much energy. Photo: JPIMedia
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