Kenny Jackett’s side need a win if they are to stand any chance of making the top two, with just Saturday’s home game against Accrington left to come.
Here’s all you need to know ahead of the game…
Pompey team news
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Omar Bogle could return to Pompey’s match-day squad for the visit of Peterborough.
The on-loan Cardiff striker, who missed the recent games against Coventry and Sunderland, had been suffering from swelling around his knee and ankle.
However, he returned to Blues training yesterday and is in contention to feature against the Posh.
Bogle, who has scored four goals in 12 appearances since his January move from the Bluebirds, will provide Kenny Jackett with extra fire-power for a game that requires maximum points.
Jackett must also decide whether to keep faith with Ronan Curtis on the left wing or recall Gareth Evans to his starting line up.
Viv Solomon-Otabor is also a consideration.
Likely starting XI (4-2-3-1)
Craig MacGillivray, Nathan Thompson, Christian Burgess, Matt Clarke, Lee Brown, Tom Naylor, Ben Close, Jamal Lowe, Brett Pitman, Ronan Curtis, Oli Hawkins. Substitutes: Alex Bass, Brandon Haunstrup, James Vaughan, Anton Walkes, Viv Solomon-Otabor, Bryn Morris, Gareth Evans
Peterborough United team news
Attacking midfielder George Cooper is expected to miss tonight’s trip to Fratton Park.
The 22-year-old damaged his knee in the first half of Saturday’s 3-0 defeat at Walsall and was replaced by Ivan Toney.
Toney is an option to come into tonight’s side for Cooper, while Lee Tomlin is another consideration.
Meanwhile, Ryan Tafazolli remains a doubt after missing that loss, so Josh Knight could again deputise.
Likely starting XI
Aaron Chapman, Jason Naismith, Josh Knight, Rhys Bennett, Daniel Lafferty, Alex Woodyard, Siriki Dembele, Louis Reed, Lee Tomlin, Matt Godden, Marcus Maddison. Substitutes: Conor O'Malley, Ben White, Callum Cooke, Joe Ward, Ivan Toney, Matt Stevens, Harrison Burrows
Dean Whitestone (Northampton)
To win: 6/10
1-0 5/1, 2-0 5/1, 2-1 6/1, 3-0 9/1, 3-1 10/1, 3-2 18/1
To win: 3/1
1-0 7/1, 2-0 14/1, 2-1 9/1, 3-0 33/1, 3-1 25/1, 3-2 22/1, 4-0 50/1
0-0 13/2, 1-1 5/1, 2-2 10/1, 3-3 28/1
Pompey stats: W 35, D14, L9
Top scorer: Jamal Lowe 17
Most assists: Ronan Curtis 15
Most appearances: Matt Clarke 56
Form: D 1-1 Sunderland (A) League One April 27; W 2-1 Coventry (H) League One April 22; W 2-1 Burton (A) League One April 19; W 4-1 Rochdale (H) League One April 13; W 3-2 Wycombe (A) League One April 6
Peterborough United stats: W22, D16, L17
Top scorer: Ivan Toney 19
Most assists: Marcus Maddison 13
Most appearances: Alex Woodyard 49
Form: L 0-3 Walsall (A) League One April 27, D 1-1 Sunderland (H) League One April 22, D 1-1 Fleetwood (A) League One April 19, W 1-0 Blackpool (A) League One April 13, W 2-0 Gillingham (H) League One April 6
Fleetwood Town v Sunderland (7.45pm)