The Foxes huffed and puffed throughout the 90 minutes but goals from Álvaro Morata and former midfielder N'Golo Kanté condemned the East-Midlanders to their third loss in four games.
Jamie Vardy did pull a goal back for the hosts in the second half but an equaliser was elusive. VAVEL UK analyse his performance and the rest of the Leicester City players:
Kasper Schmeichel - 6/10: Albeit not too bad from the Danish international, far from his best game in a Leicester City shirt. He did make a few solid stops and commanded his area well however. The 30-year-old will be disappointed in having not saved winning Kanté's strike but some forgiveness could be afforded having seen it travel through a gathering of legs. The 'keeper's distribution is still somewhat erratic.
Danny Simpson - 6/10: Again, solid if unspectacular. The defender dealt with the threats of Pedro well throughout the game. The former QPR man was also on hand to cut out a few dangerous crosses that could well have caused problems.
Harry Maguire - 7/10: Leicester's summer acquisition continues to impress the King Power Stadium faithful. The centre back was strong in the air and looked comfortable and composed on the ball. He picked out some excellent passes into the midfield. Although, he did get somewhat too confident on occasion when striding forwards and lost the ball in dangerous areas.
Wes Morgan - 6/10: The Jamaican international will be disappointed to have been out-jumped by Morata for Chelsea's opener in the closing stages of the first half. Previously, he had put in some crucial blocks for the home side. His pace still seems to be a problem as opponents look to break as the Blues did on numerous occasions. There was also occasions when his clearances left a lot to be desired - whether they spun into the crowd or to the Chelsea attackers.
Christian Fuchs - 6/10: It was a game of two halves for the Austrian at the King Power Stadium. In the first period, Fuchs struggled to deal with Victor Moses and was caught out on numerous occasions. He did provide some important attacking intent in the second half though which could have been profited from.
Riyad Mahrez - 6/10: After failing to get his desired move away from the club, it would have been interesting to see if the Algerian international showed the same desire. He was attempting to create chances for his team but was slightly frustrating as he conceded possession. The former PFA Player of the Year did however look like one of the most influential players in the Leicester City team.
Wilfred N'Didi - 7/10: Attempting to replace N'Golo Kanté was always going to be a tough task. However, the young Nigerian showed some of the characteristics of the Chelsea man. A good range of passing and an irrepressible effort allowed him to really stake a claim in the team. The 20-year-old continued to provide defensive solidarity as he displayed a promising tackling ability.
Matty James - 6/10: With the injury to Vincente Iborra and the future of Adrien Silva uncertain, James has been thrusted into the Leicester City starting XI. His desire and intelligence has never been in question but he did look off the pace against Chelsea. The ex-Manchester United midfielder was caught wrong-sided on numerous occasions and struggled to get back. The visitors' quality in midfield, with Cesc Fàbregas, Tiemoue Bakayoko and Kante, told. He was substituted late in the game.
Marc Albrighton - 6/10: The winger was replaced by Demarai Gray at half-time so was not able to really influence the game. Chelsea's wing-backs made it difficult for him to really find in the wide positions. Albrighton certainly did not lack any effort or endeavour though.
Islam Slimani - 5/10: Afforded a rare starting berth in place of the ever-reliable Shinji Okazaki, the Algerian struggled to link up efficiently with Jamie Vardy. He wasted a glorious chance to open the scoring in the first half as he was scuppered by Thibaut Courtois. The 29-year-old was also substituted at half-time.
Jamie Vardy - 7/10: The Englishman certainly looks back to his best. Vardy already has three goals to his name so far this season and took his penalty well in the second half. Earning the spot kick with his trademark pressuring, he hassled Chelsea's backline impressively. The 30-year-old looks to be rekindling some of that fire.
Demarai Gray - 5/10: The former Birmingham City youngster continues to frustrate at the King Power Stadium. Albeit gifted, Gray wasted numerous opportunities against the champions with misplaced passes and wrong decisions after he replaced Albrighton. Too often caught in a dead end, he really needs to have more of an impact if he wants to earn the game time he so vocally desires.
Andy King - 5/10: Also taking to the field after the interval, King was brought in to shore up the midfield. It was unclear where the Welshman was meant to be playing initially as he floated between defence and attack. Despite a few forward runs and odd tackles, he failed to really have an impact on the result.
Kelechi Iheanacho - N/A: The Nigerian was introduced towards the closing stages for his home debut since his switch from Manchester City. He displayed a few promising touches but really did not have enough time to make his appearance count.