Jacob Greaves’s first goal at Portman Road has given the Blues a 1-0 half-time lead over Derby County.
Town made four changes from the team which was beaten 1-0 at Preston North End a week ago with Jens Cajuste, Kasey McAteer, Ashley Young and Conor Chaplin all coming into the side.
Cajuste, making his second full debut for the club, replaced Jack Taylor in the centre of midfield with the Ireland international on the bench.
Young was given his first league start for the club at right-back with Ben Johnson among the subs.
McAteer made his full debut on the right of the forwards with Jack Clarke dropping to the bench, alongside Sammie Szmodics with Chaplin, making 150th appearance for Town under Kieran McKenna, replacing him as the number 10.
New signings Ivan Azon and Darnell Furlong were both named among the substitutes, but there was no place for either Chieo Ogbene or Luke Woolfenden.
For Derby, former Blues loanee Lewis Travis was handed his debut following his move from Blackburn, while ex-Town central defender Matt Clarke and one-time loanee Callum Elder were also in the starting line-up. Kayden Jackson was on the bench.
Two minutes into the game, referee Leigh Doughty angered the Town team and fans when he gave a free-kick against Greaves just outside the area to the right. The centre-half had challenged Bobby Clark and sent the ball into the on-loan Liverpool man’s face and away, the officials somehow deciding a foul had been committed.
Fortunately, Rhian Brewster smashed his free-kick into the Town wall and no damage was done.
On 11, Hirst played in McAteer on the right, the former Leicester man cutting back inside before sending over a cross which a defender diverted back to keeper Jacob Zetterstrom.
As the game reached the quarter-hour mark, good work from Cajuste played in Jaden Philogene on the left but the former England U21 international’s cross was too long.
Two minutes later at the other end, the Blues failed to clear following a corner and eventually the ball fell to Carlton Morris on the left of the box, but the former Luton man’s shot flew well wide having clipped off a Town player on its way,
The Blues were controlling the game, while still looking less than their coherent best at times, and in the 20th minute, Chaplin got away on the right and crossed deep, the ball falling for Leif Davis, who shot into the ground through to Zetterstrom.
A minute later, Cajuste, dictating everything from the centre of midfield, tried a one-two with his former Reims teammate Matusiwa but a defender’s toe got in the way of the Sweden international’s return ball to the Dutchman.
The game went through a scruffy spell with free-kicks and a clash between Clark and Matusiwa at a Town throw which led to an angry exchange between Young and Travis.
In the 28th minute, a well-worked Blues move saw Matusiwa find Davis out on the left and the full-back’s cross was diverted out for a corner from which Greaves rose highest but nodded over.
Three minutes later, Town played it out from the back quickly, keeper Alex Palmer moving it forward to Cajuste, who skipped past Travis and found Philogene, who in turn fed Davis breaking outside him. The ex-Leeds man’s ball found Chaplin, but the forward scuffed to Zetterstrom.
On 33, with the Blues looking increasingly dangerous, Philogene cut back from a similar area to Chaplin but this time the former Portsmouth attacker’s effort was diverted wide by Rams skipper Ebou Adams.
And from the corner, Town took the lead. Young whipped the ball in from the left, Zetterstrom completely missed it and Greaves stooped to nod in his first goal of the season and first at Portman Road ahead of the hesitant Craig Forsyth.
In the 35th minute, Elder was booked for his reaction to referee Leigh Doughty giving a free-kick against him.
Travis shot wide for the visitors then Young smashed a superb strike just past Zetterstrom’s right post off Forsyth.
Following the corner, Chaplin looped a deep ball to the far post and the Derby keeper dropped the ball under pressure from McAteer. Referee Doughty awarded a very harsh free-kick against the Irish international and then booked him for his protests.
In the 40th minute, Cajuste, looking a level above everyone else on the pitch, outrageously flicked the ball behind him to Chaplin, who moved it on to Philogene, the ball taking a deflection and forcing the ex-Aston Villa winger wide, and he shot into the side-netting.
As the half moved into injury time, Hirst seized on some loose Derby passing and played in McAteer on the right, Clarke blocking his low cross, with his hand, according to the Town winger, but not the referee.
From Davis’s corner, O’Shea headed against the far post with Greaves just unable to get onto the rebound.
That was the last action of a half the Blues had, after some battling early exchanges, controlled throughout.
Cajuste’s addition to the midfield had given Town greater cohesion in midfield with the on-loan Napoli man easily slipping back into the team alongside his teammate from Ligue 1 Matusiwa.
Chances had started to come more frequently just before the goal and the Blues had further opportunities after that, while Derby’s main threat had come from corners and free-kicks but with Town having been able to negate the danger.
Town: Palmer, Young, O’Shea (c), Greaves, Davis, Cajuste, Matusiwa, McAteer, Chaplin, Philogene, Hirst. Subs: Walton, Kipre, Taylor, Johnson, Furlong, Szmodics, Akpom, Azon J Clarke.
Derby: Zetterstrom, Sanderson, Clarke, Forsyth, Johnston, Travis, Adams (c), Elder, Clark, Brewster, Morris. Subs: Vickers, Batth, Weimann, Salvesen, Thompson, Ozoh, Jackson, Ward, Nyambe. Referee: Leigh Doughty (Blackpool).