Town boss Mick McCarthy was left bemoaning missed chances and poor defending as the Blues were defeated 2-0 at Rotherham United.
Daryl Murphy failed to take two early opportunities and had a header cleared off the line, while Millers keeper Adam Collin made an impressive save from skipper Luke Chambers.
Goals from Matt Derbyshire and ex-Blues loanee Conor Sammon netted the goals for the Millers, both from set pieces.
"We had the first chance, the first couple of chances, and of all people for them to fall to it was Murph, the top scorer and you’d expect him to score,” McCarthy said.
"Maybe having just come back after his time away, it dulls the senses slightly.
"That chance came early in the game, yes they’ve had their warm-ups, but I thought we were OK in the first 15 minutes and I didn’t see what came coming, I didn’t see us defending that badly, to be honest.
"The game was going nowhere, they scored from the freekick which was poor marking from us, which isn’t like us."
Having brought on Freddie Sears and Teddy Bishop seven minutes after the restart the Blues had their best spell following McCarthy’s half-time team-talk.
"As always, if we’re one behind [we tell them that] there are certain things that we could do better. And I thought we did that.
"We passed it better, we were a bit more considered, but even doing that I thought we were a bit more aggressive in how we played.”
He added: "When we conceded the second it was probably just after our best spell. The keeper’s made a good save, they headed one off the line, we’ve had chances, but if we defend like that and lose our markers that’ll cost us.
"We had momentum at that stage but we didn’t take our chances, that was the difference.
"It was a good save, it was a good header off the line, I can’t knock that, they’ve done their jobs. We’ve let them get away from us with the second corner. But I have to say, I thought Rotherham played well.
"There’s nothing special, strange or unusual about the deliveries, we should have dealt with them better.”
It was perhaps inevitable that Sammon should be amongst the scorers having spent the first half of the season on loan from Derby at Town.
"I was going to say it’s Sod’s Law, maybe I should say it was Murphy’s Law,” McCarthy continued. "But if he gets that chance because we don’t mark properly then he’ll put it in the net.
"I thought Conor played well, he looks like he’s played games and he’s back at it. I’m disappointed it was against us but good luck to him because he’s a great lad.”
Rotherham manager Steve Evans was delighted with his side’s display: "I think if you take it over the 95 minutes or so I think it was a wonderful performance full of all the things that we’re good at.
"Good on the ball, good in possession, fantastic industry from everyone in a Millers shirt. That’s always more difficult against an Ipswich side.
"We made a mistake and they should perhaps have been one up with less than a minute on the clock.
"We took 10 or 15 minutes to settle ourselves down and maybe we stood off them in that first 15 minutes and gave them too much respect.
"They’re a side which Mick McCarthy has put together who have real quality so you can’t over respect them. They’ve got some absolutely outstanding players I’ve no doubt they’ll bounce back because they’re full of good players.
"The overall view is that we’ve beaten an excellent side and very good football club backed by tremendous support.”