It is the first time that the sides have met for the south coast derby in more than seven years and the first time they’ve played in Portsmouth since December 2011.
One of the most heated rivalries in English football, the last time the sides met was in the Championship when David Norris rescued a late draw with a stoppage time equaliser in April 2012.
Here is everything you need to know about the game:
When do Portsmouth play Southampton?
The latest south coast derby is set to take place at Fratton Park today (September 24)
What time is kick-off?
With it being a mid-week game, the match will begin at 7.45pm on September 24.
Are there any tickets left?
No the game is completely sold out, both for home and away fans.
Tickets were snapped up the week they went on sale.
Is Portsmouth v Southampton on TV?
The south coast derby has been selected by Sky Sports for coverage on Tuesday, September 24.
So if you are not lucky enough to get a ticket for the game you will still be able to watch all the action.
Why are they playing?
Portsmouth are in League One while Southampton are currently in the Premier League, the difference in leagues is one of the reasons for the lack of south coast derbies in recent years.
However they have been drawn against each other in the third round of the Carabao Cup and that is why they are playing on September 24.
What police measures will be in place?
Hampshire Constabulary has confirmed that there will be a policing operation in place for the game later this month.
However unlike in the 2011/2012 season, a ‘police bubble’ will not be in place and Southampton fans will not be forced to travel to Portsmouth via coach only.
Hampshire Constabulary have said that the game will be the ‘biggest football policing operation’ in Hampshire.
Assistant chief constable Scott Chilton said: 'If you go there with the intention of seeking trouble, the police are prepared to be able to respond to it.
'Ask yourself, is it really worth it?’