The Championship game was due to kick off at 19:45, but still hasn't began at the time of writing.
A statement from Pompey posted on their official X account just after the game was set to start read: "There is currently an issue with the power at Fratton Park and it is being looked into.
"We will update supporters in due course."
Footage posted by fans inside the ground shows supporters holding up their phone torches in an effort to get some light inside.
20 minutes on from the original kick-off time, one stand is lit.
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Full power returned a few minutes after.
Luck hasn't been on Portsmouth's side of late, and it goes beyond them sitting in the bottom three of the Championship.
John Mousinho's side had their game at the weekend cancelled.
They were due to play Blackburn, but the match was postponed after Storm Bert caused rain water to pool in the centre of the pitch.
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