Town fell to a 2-0 home defeat to Watford, with a goal in each half securing the points for the Hornets.
Ikechi Anya curled home Watford’s opener after 18 minutes, before Nathan Chalobah sealed the win with a cool finish midway through the second-half.
Blues did have chances themselves and Tommy Smith saw a goal ruled out for offside which would have levelled the scores, but in the end the visitors were good value for their win.
Mick McCarthy made two changes to his Town squad, with Michael Chopra and Lee Martin both starting in place of Daryl Murphy and the injured Anthony Wordsworth.
The visitors started the game a lot brighter then Town and a neat flowing move involving Fernando Forestieri and Troy Deeney saw the latter work some space in the box, but he was unable to pick out the run of Jonathan Hogg after two minutes.
Hogg himself then went close for Watford two minutes later, smashing in a drive from fully 30 yards that flew just wide of Stephen Henderson’s post.
But Town were still under real pressure from Gianfranco Zola’s side and more superb, one-touch passing saw the ball worked into the path of Deeney but the striker saw his effort charged down by Luke Hyam and sail behind for a corner.
Blues did fashion a first chance of the game a minute later though, with Chopra and Carlos Edwards linking up well with
David McGoldrick but the Nottingham Forest loanee failed to test Manuel Almunia in the Watford goal.
However the visitors were still looking dangerous when they attacked and they deservedly took the lead after 18 minutes.
More good football from the Hornets saw Forestieri lay the ball off to Anya and the speed merchant created enough space inside the area to bend an effort beyond the reach of Henderson and into the far corner, although the shot did appear to take a slight deflection off a Town defender.
Town were denied what looked like a certain penalty just before the half-hour mark, after Martin was sent tumbling in the box under a challenge from Cassetti, but referee Roger East incensed the Blue Army by waving away the protests.
Ten minutes later and Almunia was forced into his first save of note, as McGoldrick stung the palms off the former Arsenal stopper with a long range effort.
Blues almost grabbed an equaliser on the stroke of half-time, but Almunia was on hand to keep out Chopra’s acrobatic bicycle-kick before the referee blew for half-time.
Town made an encouraging start to the second-half, Martin getting beyond his marker to cross but the ball wouldn’t quite spin into the path of Chopra and Lloyd Doyley was able to clear the danger.
However the visitors were always looking a threat in the final third and Anya was close to adding a second after 53 minutes, but the midfielder saw his effort loop onto the roof of the net via a wicked deflection off Smith’s heel.
Smith was then involved at the other end three minutes later, as he thought he had pulled Town level.
The defender was on hand to fire the ball home from two yards after Almunia had spilled McGoldrick’s effort but the linesman had his flag up to signal offside and chalk the goal off.
The visitors then had a great chance to double their lead after 67 minutes, as Forestieri danced his way past the challenges of Chambers and Cresswell before lashing his effort wide of the target when clean through.
However the Hornets did grab a second shortly after, as Chalobah doubled the visitors lead after 73 minutes.
Hogg played through Chalobah will a delightful through pass and the youngster remained calm to slot the ball past Henderson and into the bottom corner.
Frank Nouble, on as a second-half substitute for Town, did go close for Blues shortly after with a long range effort but his shot was always creeping wide of Almunia’s post.
Cresswell came close to grabbing a consolation for Town in injury time, but his free-kick was well held by Almunia as the visitors left Portman Road with all three points.