Kevin Bru’s 24th minute goal has given the Blues a 1-0 half-time lead at Bolton Wanderers.
Jonathan Douglas replaced Luke Hyam in central midfield in an otherwise unchanged Town side.
Hyam dropped to the bench, while Cole Skuse (toe ligament) and Daryl Murphy (calf) weren't fit enough to return.
Bolton included former Blue Liam Trotter and one-time Town trialist Lawrie Wilson in their starting XI, while former England man Emile Heskey and Josh Vela missed out.
Mick McCarthy’s men were in their orange third kit with the Trotters wearing a special dark blue strip to commemorate the 70th anniversary of the Burnden Park Disaster in which 33 fans died.
Prior to the players taking to the field the FA Cup final hymn Abide With Me was sung, then before kick-off there was a well-observed minute’s silence.
The home side created the first opening in the third minute when Liam Feeney escaped down the left and cut the ball back for skipper Darren Pratley, but the midfielder, reportedly a Town target in January, sliced his effort high and wide when he should at least have hit the target.
Wanderers continued to have the better of the opening spell and on six Mark Davies waltzed through the Town backline and into the area but failed to make significant contact on his shot and Bartosz Bialkowski saved down to his right.
On 10 Zach Clough shot over from the edge of the box with the Blues still having made little impact on the game.
Three minutes later, Clough claimed a penalty when he went to ground as he went past Kevin Foley. Referee Mark Haywood awarded a Bolton corner as the Town players protested that they ought to have had a freekick for a dive.
Following the flag-kick, the ball fell to Feeney on the left but his shot flew across the face of goal and out for a throw.
Town finally threatened in the 19th minute when Freddie Sears brought the ball inside 25 yards out and hit a shot which Bolton keeper Paul Rachubka could only parry. Derik Osede beat Brett Pitman to the loose ball but in any case the linesman had already raised his flag.
Bolton had dominated the first 20 minutes but without having anything to show for it and in the 24th minute they were made to pay.
Ben Pringle’s corner from the left reached Christophe Berra at the far post, skipper Luke Chambers having flicked on.
The Scot stabbed the ball back to Kevin Bru on the edge of the area and the Mauritius international smashed a superb strike which looped over Rachubka, hit the underside of the bar and nestled in the corner of the net.
Having gone in front via Bru’s second goal of the season, his first since the opening day, the Blues started to play with greater confidence and on 28 Pitman shot not too far wide from distance.
Trotter was unable to control a cross from the right and the ball bounced through to Bialkowski, then as the clock ticked round to 33 there was a spontaneous burst of applause in tribute to the fans who died in the Burnden Park Disaster.
The home side should have equalised on 36 when Davies cut the ball back from the right but Trotter fluffed his effort at close range and Clough looped over the bar off a Town player.
The Town goal was living a somewhat charmed life with the home side by now putting the Blues under great pressure with Berra, Douglas and others making important blocks, while Bolton players appealed for a number of penalties.
On 38 Bialkowski made a superb double stop, first blocking Dean Moxey’s effort from distance before he somehow managed to keep out Osede’s close-range rebound.
Wanderers continued the pressure - with Pringle down injured having taken a blow to the foot - and Chambers made another important block from Feeney.
Pringle was OK to carry on after treatment as was Bru after he suffered a knock on the touchline. Town saw out three minutes of injury time to retain their lead at the break.
Bolton had started the half the stronger and might well have taken the lead through Pratley early on but despite continuing to dominate didn’t seriously threaten again before Bru’s excellent goal.
Pitman went close with Town’s only other dangerous effort before a late onslaught with the Blues’ area like the Alamo at times with defenders making desperate blocks and Bialkowski making his brilliant double stop.
Bolton: Rachubka, Moxey, Feeney, Spearing, Clough, Osede, Davies, Trotter, Pratley (c), Wilson, Holding. Subs: Campbell, Madine, Danns, Wellington, Dobbie, Woolery, Finney.
Town: Bialkowski, Chambers (c), Smith, Berra, Knudsen, Foley, Douglas, Pringle, Bru, Sears, Pitman. Subs: Gerken, Digby, Hyam, Maitland-Niles, Touré, Varney. Referee: Mark Haywood (West Yorkshire).