Keith Andrews' 69th minute goal was enough to defeat Portsmouth at Portman Road after the visitors had wasted some good opportunities to take the lead.
Joel Ward and Dave Kitson came in for Erik Huseklepp and Benjani as Pompey wasted some excellent chances in the first half.
Luke Varney was sent through one-on-one with David Stockdale but the Ipswich 'keeper beat him to the ball. Kitson then should have scored but could only fire wide from Liam Lawrence's corner.
Ricardo Rocha was the next player to be guilty of missing a great header when another pinpoint delivery from Lawrence was sent straight into the arms of Stockdale.
The Irishman then crossed for Ward who could only shoot straight at Stockdale as the small contingent of Pompey fans must have been wondering how their side hadn't taken the lead.
Ipswich had barely threatened and were on the back foot at the start of the second half. Lawrence really should have given Pompey the lead but missed Ben-Haim's cross when he was completely unmarked.
David Norris also shot tamely wide following a goalmouth scramble to continue the profligacy in front of goal. Many feared that Pompey would pay for failing to take their chances and they were right to feel that way.
Town grew into the game and put the Pompey defence under pressure later in the half with Greg Halford making some important interceptions.
But the deadlock was broken in somewhat fortunate circumstances when Nathan Ellington got his goalbound header wrong from Carlos Edwards' cross but the ball was knocked on kindly for Andrews to score from close range.
Guy Whittingham and Stuart Gray urged their men forward during the later stages of the game and brought on Huseklepp and Kanu for Kitson and Rocha but could not find an equaliser as Norris headed the ball into Stockdale's arms in the last minute of stoppage time to confirm another defeat for Pompey.
Despite defeat it is encouraging to see that Pompey were at least able to carve plenty of chances away from home against a team who are now unbeaten in six matches.
It seems like we played good football and didn't deserve to lose so the new manager has plenty to build on, whoever he may be.