Jose Mourinho's defending Barclays Premier League champions are now 20 points adrift of the Foxes, who returned to the top of the table with a 2-1 victory at the King Power Stadium.
But what can be done to arrest an ever-increasing slide at Stamford Bridge? Here, Press Association Sport takes a look at the key questions the club needs to address.
STICK OR TWIST ON MOURINHO?
Owner Roman Abramovich has never been backwards in coming forwards when it comes to changing his manager - including bringing an end to Mourinho's first successful spell at Chelsea.
The Portuguese has been backed to turn things around but as the abysmal defence of their Premier League crown continues, the Russian oligarch could soon decide enough is enough.
One issue facing Abramovich is who would he bring in to replace the self-titled 'Special One' but any further embarrassment could lead to Mourinho's exit anyway
On the other hand, should he give Mourinho a chance he could very well be proved right in the long term.
WHICH PLAYERS HAVE 'BETRAYED' THE MANAGER?
Mourinho hit out at his squad following their ninth league defeat in 16 games and claimed his players had betrayed him
But who could his accusatory finger have been pointing at?
Eden Hazard collected both PFA Player of the Year and the Footballer of the Year award from the Football Writers' Association but has been a shadow of his former self so far this season.
The Belgium international came off injured at the King Power Stadium despite Mourinho asking him to stay on the pitch and, while Diego Costa remained in the game for its entirety, the Spain striker once again flattered to deceive.
Passing up a great opportunity to score, Costa also focused more on arguments with both Leicester and Chelsea players
Cesc Fabregas came on in the second half as Mourinho scarified captain John Terry but again this time last season he would have been a key figure rather than an option off the bench.
TIME TO SHAKE UP THE TEAM?
Loic Remy scored off the bench against Leicester and giving the France forward a run in the side could kick-start the Blues as an attacking force.
Meanwhile, Ruben Loftus-Cheek remains a viable option in midfield with the prospect of reuniting Terry and Gary Cahill for a prolonged period at the heart of his defence surely proving tempting to Mourinho.
Baba Rahman was an expensive summer acquisition but is yet to establish himself at Stamford Bridge - what does Mourinho have to lose in tinkering in the manner Claudio Ranieri once did?
SHOULD THEY BULK BUY IN THE JANUARY SALES?
Any business Mourinho and the club wish to conduct will not be constrained by cash and, if Abramovich keeps faith with the manager, he will look to give him a helping hand by recruiting in the new year.
Do Chelsea remain an attractive option? Maybe not to the world's elite at the moment but they will not be readily available anyway
What the club need is to recruit players of the calibre of the club but also hard-working enough to roll up their sleeves and battle - or risk 'betraying' their boss.
Source : PA
Source: PA