Svetoslav Todorov scored twice as Division One leaders Portsmouth ruined Chris Turner's Sheffield Wednesday's homecoming.
Portsmouth had started the match having seen their advantage cut to four points in the wake of nearest challengers Leicester's 2-1 home win over Rotherham.
But Todorov's brace and a second of the season for Gary O'Neil re-established their seven-point lead at the top of the table.
Even after losing influential skipper Paul Merson in the 24th minute to what seemed to be an ankle injury, Portsmouth were still far too strong for Wednesday.
Harry Redknapp's side took the lead after just 10 minutes, when Todorov lashed home his ninth goal of the season after Kevin Pressman had failed to get any distance on his punched clearance.
But the Owls equalised on 27 minutes when Leon Knight flicked Lloyd Owusu's knock-on over the advancing Shaka Hislop.
Todorov restored Pompey's lead when he bagged his 10th of the campaign with a cool finish beyond Pressman.
Todorov then started the 63rd-minute move that ended with Gary O'Neil converting the simplest of chances from six yards.
Sheff Wed: Pressman, Crane, Haslam, Bromby, Geary, Armstrong, Quinn, Beswetherick, Sibon, Owusu, Knight. Subs: Stringer, Hendon, Hamshaw, Morrison, Donnelly.
Portsmouth: Hislop, Diabate, Primus, Foxe, De Zeeuw, Taylor, Harper, Robinson, Merson, Todorov, Pericard. Subs: Kawaguchi, Crowe, Burchill, Pitt, O'Neil.
Referee: P Danson (Leicestershire).