Barnsley began life after Andy Ritchie with a victory thanks to Grant McCann's 92nd-minute winner.
McCann had only joined Barnsley on loan from Cheltenham on Thursday but he quickly made his mark drilling a fine left-footed shot past Lewis Price.
Earlier in the second half, McCann had served notice of his shooting ability when he hit a fierce left-foot volley which flew inches over Price's bar.
Ipswich struggled in attack and rarely tested Barnsley keeper Nick Colgan.
Barnsley caretaker boss Simon Davey:
"It was always going to be a hard game, and we were under no illusions about the task facing us - given our position in the league.
"I said before the game that if we win and we win 'ugly', we'll take that.
"I'd rather do that than pass a team off the park and lose. It was a sweet pearl to get the goal two minutes into injury-time, and I'm proud of them."
Ipswich boss Jim Magilton:
"It was an awful game. There was no football played, and we were poor. We didn't pass the ball at all.
"Neither goalkeeper had to make a save, and we fell asleep when it really mattered yet again.
"Barnsley are fighting for their lives. We expected a backlash - and we got it. Ultimately, we lost the game because we switched off."
Barnsley: Colgan, Hassell (Austin 74), Paul Reid, Kay, Heckingbottom, McCann, Togwell, Wallwork, Hayes (Kyel Reid 81), Knight, Nardiello (Richards 63).
Subs Not Used: Letheren, Howard.
Booked: Kay, Wallwork.
Goals: McCann 90.
Ipswich: Price, Bates (Garvan 66), Bruce, De Vos, Harding, Roberts (Williams 73), Legwinski, Walton, Richards, Macken (Haynes 59), Lee.
Subs Not Used: Supple, Naylor.
Booked: Harding, Garvan.
Ref: E Ilderton (Tyne & Wear).