Pompey have more than 9,000 tickets left for tomorrow tonight’s clash with Birmingham.
So far, only 11,261 seats have been sold, including 485 visiting supporters.
The Blues have cut prices for the fixture, offering Four for £44, consisting of two adults and two juniors attending for just £44.
In addition, there is Two for £25, which is one adult and one junior for £25.
The offers apply to all areas, except the family enclosure and Milton end.