The opening game of the season against Morecambe has produced the highest gate so far (6004), but there were only 131 visiting supporters on that day.
To date, Pompey have sold around 650 of their initial 1300 allocation, but the Fratton Park club will be offered up to 1900 tickets for the Osmond Stand.
Town supporters are being urged to secure their seats as soon as possible to avoid disappointment on the day. Tickets for the Portsmouth game, Accrington Stanley (Dec 26), Blackpool (Dec 31) are currently on sale at Early Bird prices.
You can book you match tickets online, by calling the ticket office on 01472 605050, or by visiting the ticket office at Blundell Park.