The visitors, meanwhile, will be looking to continue their promising run of form, having avoided defeat in each of their last four matches.
Match preview
After losing four consecutive matches, Peterborough have got back on track with three straight victories, beginning with a 3-0 win over Blackpool in the EFL Trophy semi-finals.
The Posh went on to record a 1-0 victory in the derby with Cambridge United, before they edged out Exeter City via a 2-1 scoreline in Saturday's home fixture.
Although Ephron Mason-Clark saw his opener cancelled out by Tom Carroll, Peterborough still managed to pick up all three points thanks to Kwame Poku's 68th-minute winner.
The fifth-placed side are now five points clear of Oxford United in seventh position, while they are seven points adrift of the automatic promotion places.
With the Posh looking to keep their promotion hopes alive, they will take encouragement from the fact they have won each of their last four home league games against the Cobblers.
Northampton will be confident they can trouble Darren Ferguson's side after taking eight points from their previous four matches.
In their most recent outing, Louis Appere netted an 80th-minute equaliser to ensure Saturday's home meeting with Charlton Athletic finished in a 1-1 draw.
That result took Northampton's tally to 49 points, leaving them in 12th position ahead of Tuesday's trip to the Weston Homes Stadium.
The Cobblers will now turn their attention to Saturday's contest, where they will have the opportunity to record a second straight away win after beating Burton Albion 2-0 in their most recent road trip.
Jon Brady's side also have the chance to complete a league double following their narrow 1-0 victory in August's reverse fixture.
Peterborough United League One form:
L
L
L
L
W
W
Peterborough United form (all competitions):
L
L
L
W
W
W
Northampton Town League One form:
D
L
W
D
W
D
Team News
Peterborough midfielder Jeando Fuchs is expected to miss the rest of the season after picking up a knee injury against Cambridge United last month.
The hosts are also unable to call upon goalkeeper Will Blackmore and forward Jacob Wakeling due to their injury issues.
Forward Ricky-Jade Jones is a doubt after his substitute appearance against Exeter was cut short in stoppage time.
Northampton, meanwhile, are contending with an injury list that features Akin Odimayo, Danny Hylton, Ali Koiki and Tyler Magloire.
Appere could be rewarded with a starting place after he came off the bench to score the all-important equaliser in Saturday's draw with Charlton.
Ben Fox dropped out of the starting lineup at the weekend, but the midfielder could be brought straight back into the side for Tuesday's home fixture.
Peterborough United possible starting lineup:
Steer; Katongo, Knight, Edwards, Burrows; Kyprianou, Collins; Poku, Randall, Mason-Clark; Mothersille
Northampton Town possible starting lineup:
Moulden; Willis, Sherring, Guthrie, Brough; Fox, Hondermarck; Bowie, Leonard, Pinnock; Simpson