Jesse Marsch's first game as Leeds boss ended in defeat as Harvey Barnes scored the only goal to give Leicester their second Premier League win of the week.
The winger produced Leicester's one moment of attacking quality with a precise angled finish midway through the second half of a game in which they had been largely second best.
It has been an emotional week for Leeds since the departure of Marsch's much-loved predecessor Marcelo Bielsa following a chastening month in which they conceded 20 goals and picked up only one point from a possible 15.
But they produced a lively and energetic display at the King Power Stadium that showcased a change of shape and the hard-pressing, direct football preferred by their American manager.
Better finishing from Jack Harrison, Rodrigo, Junior Firpo or Raphinha would have given Leeds a win they so desperately need to ease their relegation concerns.
Having spurned them, they left themselves vulnerable to a decisive moment like the one Barnes produced.
Victory lifted Leicester to 10th in the table. Leeds remain two points above the bottom three, having played two games more than 18th-placed Burnley.
No points but plenty of positives for Marsch
Whether you have Bielsa, Marsch or any other manager in charge, the old adage remains true: if you don't take your chances when on top, you risk being punished.
It was a recurring failing of Leeds under Bielsa that they failed to make good on the bountiful chances they often produced in games long before they were shipping goals to the tune of 20 in a month.
While Marsch changed a number of things in his first game in charge - a new 4-2-2-2 formation and quicker play through the middle - it was the old problem of conversion that cost Leeds.
Kasper Schmeichel can take some credit for repelling the visitors, producing saves to deny Dan James, Harrison, Rodrigo and, in the best of all from close range, Raphinha.
Caglar Soyuncu was also on hand to brilliantly block Junior's goalbound shot from inside the box.
This all set up Leicester, who until then had offered very little barring the occasional threat of the returning Jamie Vardy getting in on goal with long balls over the top.
Barnes is a player building his reputation weekly and, after sharing a one-two with Kelechi Iheanacho, he slotted a low shot across goal and past the diving Illan Meslier.
Leeds continued to press forward, but their moment had passed and Leicester were able to see the game out to add another three points to those earned at Burnley on Tuesday.
Marsch gathered his players in a huddle in the centre circle at full-time. His message will surely have been to focus on the multiple positives.
No points, but plenty to take forward into a run of crucial games beginning with Aston Villa and Norwich at home next week.
Player of the match
JamesDaniel James
Leicester City
Squad number1Player nameSchmeichel
Squad number7Player nameBarnes
Squad number9Player nameVardy
Squad number11Player nameAlbrighton
Squad number22Player nameDewsbury-Hall
Squad number14Player nameIheanacho
Squad number4Player nameSöyüncü
Squad number37Player nameLookman
Squad number33Player nameThomas
Squad number18Player nameAmartey
Squad number25Player nameNdidi
Squad number20Player nameChoudhury
Squad number8Player nameTielemans
Squad number24Player nameMendy
Leeds United
Squad number20Player nameJames
Squad number2Player nameAyling
Squad number15Player nameDallas
Squad number1Player nameMeslier
Squad number21Player nameStruijk
Squad number22Player nameHarrison
Squad number5Player nameKoch
Squad number10Player nameRaphinha
Squad number3Player nameFirpo
Squad number19Player nameRodrigo
Squad number30Player nameGelhardt
Squad number43Player nameKlich
Squad number4Player nameForshaw
Squad number11Player nameRoberts
Line-ups
Leicester
Formation 4-3-3
1Schmeichel
20Choudhury18Amartey4Söyüncü33Thomas
8Tielemans25Ndidi22Dewsbury-Hall
11Albrighton9Vardy7Barnes
1Schmeichel20ChoudhurySubstituted forLookmanat 61'minutes18Amartey4Söyüncü33Thomas8Tielemans25NdidiBooked at 53minsSubstituted forMendyat 76'minutes22Dewsbury-Hall11Albrighton9VardySubstituted forIheanachoat 61'minutes7BarnesSubstitutes
12Ward14Iheanacho17Pérez23Vestergaard24Mendy29Daka37Lookman42Soumaré62BruntLeeds
Formation 4-2-3-1
1Meslier
15Dallas2Ayling21Struijk3Firpo
43Klich5Koch
10Raphinha19Rodrigo22Harrison
20James
1Meslier15Dallas2Ayling21StruijkBooked at 9mins3Firpo43KlichSubstituted forForshawat 70'minutesBooked at 71mins5Koch10Raphinha19RodrigoSubstituted forGelhardtat 63'minutes22HarrisonSubstituted forRobertsat 76'minutes20JamesSubstitutes
4Forshaw9Bamford11Roberts13Klaesson30Gelhardt35Cresswell38Summerville42Greenwood46ShackletonReferee:David CooteAttendance:32,236Live Text
Match ends, Leicester City 1, Leeds United 0.
Second Half ends, Leicester City 1, Leeds United 0.
Corner, Leeds United. Conceded by Daniel Amartey.
Attempt blocked. Joe Gelhardt (Leeds United) left footed shot from the centre of the box is blocked. Assisted by Raphinha.
Attempt saved. Youri Tielemans (Leicester City) right footed shot from outside the box is saved in the top centre of the goal. Assisted by Marc Albrighton.
Attempt blocked. Ademola Lookman (Leicester City) right footed shot from outside the box is blocked.
Corner, Leicester City. Conceded by Pascal Struijk.
Attempt blocked. Harvey Barnes (Leicester City) right footed shot from outside the box is blocked. Assisted by Ademola Lookman.
Offside, Leicester City. Kiernan Dewsbury-Hall tries a through ball, but Kelechi Iheanacho is caught offside.
Youri Tielemans (Leicester City) wins a free kick in the defensive half.
Foul by Robin Koch (Leeds United).
Attempt missed. Robin Koch (Leeds United) with an attempt from the centre of the box misses to the left following a corner.
Corner, Leeds United. Conceded by Ademola Lookman.
Luke Thomas (Leicester City) wins a free kick in the defensive half.
Foul by Joe Gelhardt (Leeds United).
Substitution, Leicester City. Nampalys Mendy replaces Wilfred Ndidi.
Substitution, Leeds United. Tyler Roberts replaces Jack Harrison.
Foul by Daniel Amartey (Leicester City).
Daniel James (Leeds United) wins a free kick in the defensive half.
Corner, Leicester City. Conceded by Junior Firpo.
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