Leicester's chances of Premier League survival suffered a blow as they collapsed to a 5-3 at Fulham on Monday.
Willian and Tom Cairney both scored twice for the Cottagers as they closed in on a top-half finish on their return to the top flight.
But the Foxes, who won the Premier League in stunning fashion in 2016 and lifted the FA Cup two years ago, are staring relegation in the face.
Leicester are outside the relegation zone only on goal difference.
They could end the day in the bottom three should Everton win at Brighton and Nottingham Forest pick up at least a point at home to Southampton.
Dean Smith's men also face a tough run-in with Champions League-chasing Liverpool and Newcastle to come before ending the season at home to West Ham.
Only Leeds and Bournemouth have conceded more goals than Leicester in the Premier League and defensive deficiencies were again their undoing at Craven Cottage.
Willian's free-kick from out wide was allowed to sail beyond everyone to open the scoring just 10 minutes in.
Fulham were still without top scorer Aleksandar Mitrovic, serving an eight-game ban for pushing a referee.
But his deputy Carlos Vinicius was given acres of space to run in behind the Leicester defence and fire home the second from Harry Wilson's pass.
Two cool finishes from Cairney either side of half-time then made it 4-0 before the visitors' showed what they are capable of going forward.
Harvey Barnes fired home from James Maddison's pass and Leicester could have been back in the game but Jamie Vardy's penalty was saved by Bernd Leno.
Fulham swiftly went up the other end to make it 5-1 as Willian smashed home another strike from outside the box.
Maddison had seen a penalty saved in a 2-2 draw with Everton last week, but found the net when he took back responsibility from Vardy for Leicester's second penalty of the afternoon.
Barnes then pounced to make it 5-3 after a calamitous defensive mix-up between Shane Duffy and Leno.
But it was too little, too late for Leicester who face an anxious wait to see where they will sit in the table before they are in action again in a week's time against Liverpool.
kca/pb