David McGoldrick's 85th-minute goal secured a vital 1-0 victory for relegation-threatened Ipswich and dealt a blow to Leicester's promotion aspirations.
A finely balanced game, which contained some neat play but very little in the way of clear-cut chances, could have gone either way and appeared set for stalemate until McGoldrick converted well the second goal of his loan spell from Nottingham Forest.
Only time will tell how valuable that late goal could be with Town now six points clear of the npower Championship drop zone and the Foxes still riding high in the play-off places.
The best of very few chances had previously fallen to Leicester striker Harry Kane, on loan from Tottenham, just before the hour mark but he could only send his shot wide when latching on to Luke Chambers' under-hit back pass.
For Leicester, it was a disappointing end to a day which started with the announcement of a significant loss of £29.7million for the financial year ending 31 May 2012, an increase of £14.5m on the previous 12 months.
A goalless draw appeared on the cards pre-match with Ipswich the lowest scorers in the second tier and Leicester boasting the meanest defence, and it was clear very early on there was very little prospect of the 6-0 victory City recorded in the reverse fixture in November.
Both sides, each unchanged from their last outing, immediately set a pattern for the game with plenty of passing football on show albeit with very little in the way of goalmouth action.
The first chance of any note finally arrived in the 22nd minutes, Kane seeing his effort deflected harmlessly wide.
Despite the lack of excitement in the final third, Town boss Mick McCarthy will have been delighted with what he was seeing against the promotion-chasing visitors amid a very even first half.
It was Kane who created a clear-cut opening just before the half-hour mark but, having turned Town's defence inside out, could only drill wide from 10 yards.
Paul Konchesky fired just over as Leicester continued to fashion the better chances although Kasper Schmeichel was called upon to keep out Chambers and McGoldrick.
And as the half-time whistle blew it was down to McCarthy and Foxes counterpart Nigel Pearson to conjure up a plan to strike the single blow which was likely to settle matters.
Leicester boasted the best second-half record in the Championship going into the game but it was Town who flew out of the blocks, Schmeichel saving well from McGoldrick.
Yet the hosts gifted City a golden opportunity to break the deadlock in the 57th minute.
A terrible back pass from Chambers put Kane clean through but he could only send his effort the wrong side of a post.
The miss looked set to prove costly with the second period following a similar pattern to the first, easy to watch but containing very little to get excited about.
Yet all that changed in the 85th minute as McGoldrick punished Foxes defender Wes Morgan for his sloppy defensive play to convert left-footed from 12 yards.
Leicester threw plenty forward in search of a leveller but it failed to come.