Pompey are on a run of four successive wins in League One, while also extending their league unbeaten run to seven games with a win over Gillingham on Saturday.
However, there was a shock as some of the Blues’ promotion-chasing rivals slumped down the form table.
We take a look at which teams are in and out of form, based on the last six League One games.
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21. Wigan Athletic - 13 points
Leam Richardson’s side sit joint-top of League One having lost once in their last six games, a final-minute win against promotion rivals Plymouth sees the Latics fourth in the form table. (Photo by Dan Mullan/Getty Images) Photo: Dan Mullan
22. Oxford United - 14 points
Karl Robinson’s side sit joint-second in the form table as they’re unbeaten in their last six. Their dropped points came against Rotherham and Ipswich in two goalless draws. (Photo by Richard Heathcote/Getty Images) Photo: Richard Heathcote
23. Rotherham United - 14 points
The Millers have also picked up 14 points from their last six and sit top of League One. They're undefeated in their last 16 fixtures, which includes a 0-0 draw on Saturday against Oxford United. (Photo by Jacques Feeney/Getty Images) Photo: Jacques Feeney
24. Portsmouth - 16 points
Danny Cowley’s side sit top of the form table and have been on a recent resurgence since a difficult start to League One. Cowley’s men are unbeaten in their last six and have dropped their only points to Cheltenham. (Picture: Jason Brown/ProSportsImages) Photo: Jason Brown