The Posh are currently sat in eighth place in the League One table, while Pompey are a point further back in 10th position.
Match preview
Darren Ferguson returned for a fourth spell as Peterborough boss after Grant McCann was sacked following a 3-0 defeat to Wycombe Wanderers.
In his first game back in charge, Peterborough secured a 2-0 away victory over Port Vale thanks to a second half brace from Ephron Mason-Clark.
After games with Charlton Athletic and Burton Albion were postponed, Posh will be well-rested ahead of Saturday's game, which represents Ferguson's first home match since returning to the Peterborough dugout.
Peterborough are currently five points adrift of the playoffs, and with sixth-place Barnsley not in action at the weekend, they have the opportunity to reduce that gap to just two points with a win.
Although they lost 2-1 to Portsmouth in their away meeting earlier in the season, Peterborough have won their last three competitive home games against Saturday's opponents.
Meanwhile, John Mousinho has enjoyed the perfect start to his managerial career, after leaving his role as player-coach at Oxford United to become Portsmouth's head coach.
Mousinho's tenure began with a 2-0 home win over Exeter City last weekend, and Pompey managed to replicate that scoreline when they made the trip to the Highbury Stadium to face Fleetwood Town on Tuesday.
Colby Bishop gave Pompey the lead two minutes before half time, while Joe Pigott doubled the advantage in the 83rd minute to end a five-game winless away run in all competitions.
Like their hosts, Portsmouth are also looking to mount a playoff push, and a third consecutive victory would move them to within three points of the top six.
Impressively, Pompey have kept six clean sheets in their 12 away matches this season - only Sheffield Wednesday have recorded more shutouts on their travels in League One.
Peterborough United League One form:
L
L
D
W
L
W
Portsmouth League One form:
D
D
L
L
W
W
Portsmouth form (all competitions):
L
L
L
L
W
W
Team News
Although Peterborough have reported no new injury concerns, they are still unable to call upon Kell Watts, who is ruled out with a knee problem.
Ollie Norburn and Joe Tomlinson are both nearing a return to training, but the pair will not be involved against Portsmouth.
After having plenty of time to prepare for Saturday's encounter, Ferguson could be tempted to select the same lineup that started the 2-0 victory over Port Vale.
As for the visitors, Ronan Curtis is unlikely to feature after he picked up an ankle injury in Tuesday's win against Fleetwood, which could result in Dane Scarlett being presented with a starting opportunity.
Portsmouth are also expected to be without the services of Jayden Reid, Clark Robertson, Joe Rafferty and Tom Lowery due to injury issues.
Louis Thompson could be brought into the midfield to replace the suspended Joe Morrell, who was sent off for two bookable offences in midweek.
Peterborough United possible starting lineup:
Norris; Thompson, Kent, Edwards, Butler; Taylor, Kyprianou; Ward, Poku, Mason-Clark; Clarke-Harris
Portsmouth possible starting lineup:
Macey; Swanson, Raggett, Towler, Ogilvie; Thompson, Pack, Tunnicliffe; Dale, Curtis, Bishop