Michael Chopra's first-half goal gave Ipswich victory and piled on the misery for crisis club Portsmouth, who applied for administration earlier on Tuesday.
Ipswich's Damien Delaney hit the bar with a header after just five minutes.
Chopra then broke the deadlock, reacting quickest when Daryl Murphy nodded against the post.
The home side got the ball in the net after the break from Greg Halford's long throw, but referee Darren Deadman ruled that no-one else had touched it.
Portsmouth boss Michael Appleton felt the goal should have stood, because he felt Ipswich's Jay Emmanuel-Thomas touched the ball on its way in.
Pompey's financial problems mean a 10-point penalty is imminent - which would leave Michael Appleton's side 21st in the Championship and above the relegation zone only on goal difference.
They got off to a terrible start on the field too, and had to survive a wave of Ipswich attacks straight from kick-off.
Delaney's header skimmed the bar, Pompey keeper Stephen Henderson almost spilled a Jay Emmanuel-Thomas shot, and a Martin free-kick fizzed over.
Ipswich did take the lead on 13 minutes when Murphy's header hit the woodwork and the ball fell for Chopra to nudge it over the line for his 11th goal of the season and fourth in the last three games.
Pompey's fans had turned out in force to lift their side but they had precious little to encourage them.
Futacs almost levelled against the run of play when he made the most of a defensive error to take a shot that was deflected wide.
In the meantime, Ipswich were still pouring forward and should have extended their lead.
Martin fired over from an Andy Drury pull-back, before Drury himself fired wide, and the same two players were denied again late on when Martin hit the post and Henderson denied Drury.
The result was never in doubt, though, despite those Pompey claims for a goal.
After a run of two wins in 16 games, Paul Jewell's side have now won their last three matches to climb above Pompey to 17th in the table.
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Portsmouth boss Michael Appleton:
"I hope the referee is disappointed with the decision he made. I was so disappointed for the fans because they came in their droves and it would have been nice to get something out of the game for them.
"Basically Emmanuel-Thomas kneed the ball into his own goal. I thought it was a goal right away because the ball changed angles as it went into the back of the net.
"The boy knew as well. You could tell in his face that he had scored an own goal."
Ipswich Town manager Paul Jewell:
"It was a difficult night to come here with everything that's going on at this football club. It's obviously a tough time for everyone connected to it and especially the supporters.
"We knew they would be as one, back their team and we knew we had to start quick and not let them get any momentum. We started the game very fast and very sharp. The goal was the least we deserved.
"On the balance of play, I think we fully deserved to win. On paper, it may be a 1-0, but we could have scored four or five."