Despite a promising first-half performance by the Terriers, Riyad Mahrez' 53rd-minute curling opener set the tone for the rest of proceedings.
The Algerian winger set up Islam Slimani less than 10 minutes later to double the home side's lead before Marc Albrighton rounded off the scoring in injury time, delivering another loss on the road to an evidently-fatigued Huddersfield.
Here's how the visitors rated after kicking off 2018 in the worst possible way:
Schindler's tackling one of the few positives
Jonas Lössl - 7: Lössl has been brilliant in his debut season in England and will be expected to turn his loan from 1. FSV Mainz 05 into a permanent move ahead of the 2018-19 campaign.
The Dane made more good stops at the King Power and wasn't at fault for any of the three goals shipped, so an unlucky day out.
Tommy Smith (Laurent Depoitre, min. 82) - 7: The club captain defended well before being substituted with less than 10 minutes to go, as well as looking dangerous when marauding down the right flank, as per usual.
He took one of Leicester's better players this season, Marc Albrighton, reasonably out of the game when on the pitch, and the winger coincidentally broke loose and scored while he was watching from the bench.
Christopher Schindler - 7: Schindler has perfectly justified his label as a fan favourite not just during Huddersfield Town's spell in the Premier League, but since his arrival, and he put in another stand-out performance on Monday, despite the scoreline.
Some of his tackling was simply superb and it comes as no surprise that he's being linked with a move away, clubs will certainly want him in their back line.
Mathias Jørgensen - 6: Like too many of the Huddersfield players, 'Zanka' looked good in the first half where the team looked like going ahead, but then tailed off after the break.
Arriving from FC Copenhagen in the summer, it wouldn't be surprising if he hasn't yet grasped the required workload of the brutal winter period in England - that'd certainly explain his recent 'iffy' showings.
Chris Löwe (Scott Malone, min. 76) - 7: Löwe did all he could to keep Riyad Mahrez out of the game, and succeeding for the majority of his time on the pitch, but was undone for the Foxes' opener.
Mahrez easily lost the German full-back before superbly bending the ball around Jonas Lössl in the moment that was the catalyst of Town's downfall on the day.
Midfield duo overrun once fatigue kicked in
Danny Williams - 7: It was a routine performance by Williams really; consisting of energy, willingness to put his body on the line and terrific shielding of the defensive line.
The American attempted to take most of the defensive responsibilities upon himself so partner Mooy could do his own thing on the offensive, and was one of the away side's more impressive players.
Aaron Mooy - 6: Similarly to Jørgensen, Huddersfield's star man started the match off solidly and looked completely at it, however, then his performance level sufficiently dropped.
There was constant uncharacteristic sloppiness by Mooy but fans shouldn't be worried, it's about time he had a rest and that should come at the weekend against Bolton Wanderers.
Limited attacking spark throughout
Rajiv van La Parra - 6: There was the usual striving work rate on show from van La Parra at the start of the match, but it didn't take long for him to run out of gas.
And once his stamina went astray, his creativity was none existent which resulted in poor Mounié getting no service for almost the whole match considering Ince and Lolley were equally as knackered.
Tom Ince - 5: Ince bagged his first Huddersfield Town goal last week when Stoke City visited the John Smith's Stadium, but hasn't managed to match that performance in the couple of outings since.
It was just a repetitive story, as in the centre-attacking-midfielder couldn't find the energy in the second half to be productive whatsoever and is also likely to receive a rest at Bolton - it's a mystery how he wasn't taken off.
Joe Lolley (Collin Quaner, min. 59) - 5: Lolley has only recently been introduced to the first team fray in the Premier League due to injury problems, and has impressed as part of the attacking trio behind the sole striker.
He really struggled to get involved here though, and was subsequently taken off for Quaner after an hour who was similarly effectively courted by Danny Simpson.
Steve Mounié - 6: Nothing was happening for the Beninese striker; no service, not a great deal of effort and a prominent failure to hold up the ball to get his fellow attackers involved.
Attacking substitutes fail to make an impact
Collin Quaner (Joe Lolley, min. 59) - 5: Having turned into a regular fixture in the Huddersfield team over the past few weeks, Quaner was similarly as disappointing as Lolley after replacing the Englishman at the hour mark.
Scott Malone (Chris Löwe, min. 76) - 5: Malone is known to be a more attacking left-back than Löwe so David Wagner made this change with hope it'd offer more attacking prowess, the damage was already done though.
Laurent Depoitre (Tommy Smith, min. 82) - 5: The match was long gone at 2-0 when the Belgian striker came on and he received no service as a result.