Much of the talk beforehand was how City would cope with in-form Forest's pace and movement but for much of the game the reverse was true with Leicester imposing their own fluent brand of football in a fiercely fought contest.
Leicester's win was all the more creditable because they did it without regular strikers Paul Dickov, who was suspended, and the injured Brian Deane.
Added to those absentees was flu victim Andy Impey. Forest, on the other hand, were able to choose from a full squad.
The Foxes were at their neighbours from the off with Muzzy Izzet blazing over the bar with a speculative shot.
Then the referee waved aside strong penalty claims after Mathieu Louis-Jean appeared to barge over Alan Rogers inside the area.
Having ridden City's early storm Forest began to edge forward but they struggled to find any rhythm with Leicester quick to close them down at every opportunity.
After 20 minutes Trevor Benjamin held off Michael Dawson to crack in a 25-yard shot that flew over the bar.
Benjamin then held the ball up well before laying it off to Rogers, who shot over from 22 yards.
Forest had to wait until the half-hour mark for a shot on goal with Ian Walker comfortably dealing with Andrew Reid's long-range effort.
City were finally rewarded on 37 minutes with a goal from 19-year-old youth academy graduate Tommy Wright, his second of the season.
Michael Dawson's headed clearance from a Rogers throw fell to Jordan Stewart who drilled in a shot from 22 yards. Darren Ward could only parry the effort into the path of Wright who side-footed home from five yards.
Moments later Forest broke swiftly but the move ended with David Johnson shooting over from a good position. It was to be the clearest chance the visitors were to produce all night.
The second half was a more even contest.
After 57 minutes Darren Huckerby tried his luck from 20 yards but his shot lacked the accuracy to trouble the Leicester keeper.
James Scowcroft and Izzet were dominating midfield and on the hour mark Ward came to Forest's rescue with a flying fingertip save to keep out Stewart's rising 25-yard drive.
In the 66th minute Reid sent Harewood scampering clear but his shot from an acute angle was gathered comfortably by Walker.
Forest continued to work hard but they struggled to find a way through City's resolute rearguard.
Two minutes from the end Paul Hart's last throw of the dice saw him replace the ineffectual Johnson with Mark Lester but he was able to make no headway and it was Leicester who ran out worthy winners.