Pompey will look to make it six wins from their past seven matches when they host Reading on Saturday (3pm kick-off).
John Mousinho’s men have got a six-point lead at the summit – seven over third spot – although the sides immediately below have at least one game in hand.
Their next opponents are also enjoying some good form, which has helped them pull away from the drop zone.
The Royals are unbeaten in six games to move up to 16th position in League One and are four points ahead of the bottom four.
It might have been an even rosier picture, but they conceded a stoppage-time equaliser at Fleetwood earlier in the week.
The recent upturn for Rubén Sellés’ men has come amidst a sea of protests from supporters, who are upset about the club ownership.
A points deduction last season saw them relegated from the Championship, while four more have been taken off this term.
Pompey overturned a two-goal deficit to win in Berkshire back in October, courtesy of strikes from Tino Anjorin, Colby Bishop and Terry Devlin.
You have to go back to the summer of 2011 to find the last league contest at Fratton Park, when Dave Kitson netted the Blues winner against his former club.
TEAM NEWS
Tom Lowery is the latest player to book a spot in the treatment room after injuring his hamstring on Tuesday night.
Tino Anjorin (hamstring), Terry Devlin (shoulder), Josh Dockerill (knee), Tom McIntyre (ankle), Joe Morrell (knee), Regan Poole (knee), Alex Robertson (hamstring) and Ben Stevenson (knee) are also sidelined.
Sam Smith and Andy Yiadom should be fit enough for the visitors, but Jeriel Dorsett (ankle) and Tom Holmes (back) are expected to miss out.
VIEW FROM THE DRESSING ROOM
Read the thoughts of John Mousinho and Marlon Pack ahead of the game.
HEAD TO HEAD
Overall
Pompey: 22 wins
Reading: 12 wins
14 draws
At Fratton Park
Pompey: 13 wins
Reading: 4 wins
7 draws
TICKETS
Seats have sold out, but the ticket exchange remains open until 11.59pm on Friday, so keep checking to see if any become available.
If you are coming to the game, click here to find out what is happening around the ground ahead of kick-off.
MATCH COVERAGE
Domestic iFollow subscribers can listen to live commentary from Andrew Moon and Guy Whittingham by signing into their account and visiting the match centre from around 2pm on Saturday.
Overseas subscribers and match pass holders can watch all the action live, with replays and accompanying commentary.
Click here for more information about using iFollow on a matchday and click here for information on downloading the app, so you can access content on your mobile device.
We will have key updates throughout the game on Twitter and a detailed blog via the match centre.
There will be post-match reaction on the website and our official YouTube channel, with highlights to follow on Sunday.
Local listeners can hear commentary by tuning in to either BBC Radio Solent or Express FM (not available online).
ALSO IN LEAGUE ONE
All games kick-off at 3pm
Bolton v Charlton
Carlisle v Cambridge
Cheltenham v Port Vale
Derby v Stevenage
Fleetwood v Barnsley
Leyton Orient v Burton
Lincoln v Exeter
Northampton v Bristol Rovers
Peterborough v Blackpool
Shrewsbury v Wigan
Wycombe v Oxford
MEMORABLE MEETING