The Cottagers sit bottom of the table after conceding 31 goals in their opening 12 games and with only one win all season since winning promotion from the Championship.
With survival now the aim of the game, what can Fulham expect as the former Chelsea boss returns to west London?
Ranieri has usually played a 4-4-2 formation wherever he has gone. Fitness and pressing in midfield are trademarks of his teams, and he now has the international break to drill his new squad on his preferred tactics.
Fulham will look to start with two strikers, with either Andre Schurrle or Luciano Vietto likely joining Aleksandar Mitrovic up front.
Vietto may well be the key to Ranieri’s 4-4-2. A striker who can create chances for a more natural finisher was an important asset whilst he was manager at Leicester and Chelsea. Shinji Okazaki was the unsung hero when Leicester won the league and Eidur Gudjohnsen was a key member of his Chelsea team.
The Argentine has already provided four assists in the league so far this season so he could be ready made for Ranieri’s style by playing as the second striker.
A new-look midfield
Ranieri has always had high-class midfielders at his disposal; at Chelsea he had Claude Makelele and at Leicester he had N’Golo Kante.
Holding midfielders with a high work-rate are the key to success under Ranieri and he will hope to unlock that from record signing Andre-Frank Zambo Anguissa after his £30 million arrival on deadline day.
If that fails, he could look to go down a different route with Stefan Johansen. The Norway captain has been on the fringes at Fulham this season but his impressive fitness and work rate could see him brought in as an important player under the new manager.
If Fulham are to play Anguissa or Johansen in a 4-4-2, that leaves one spot open for either Jean Michael Seri or Tom Cairney. Both were expected to light up the Premier League this season but neither man has found any type of form.
The thing Fulham have been lacking most is defensive stability after conceding 31 goals in just 12 Premier League games.
At almost every club he has managed, Ranieri has employed no-nonsense centre-backs whose primary role is to just defend. Robert Huth embodies this more than anyone else after being utilised at both Leicester and Chelsea.
Ranieri has been a fantastic defensive manager in the Premier League, never conceding more than 40 goals when he has had a full season in charge of either Chelsea or Leicester.
The arrival of the Italian could spell the end of Denis Odoi as a centre-back. The Belgian is small for a centre-back, standing at only 5ft 10in and was favoured by Jokanovic for his ball-playing abilities, something which Ranieri has never prioritised in defence.
Alfie Mawson should immediately become first-choice centre-back under the new regime. The 6ft 2in Englishman fits the mould of what the former Chelsea manager wants from his centre-backs.
The other spot will go to one of Tim Ream, Maxime Le Marchand or Calum Chambers. All three players can play the role that the new manager would want but Ream may be the man he goes for.
Ream was a rock at the back for Fulham last season, never more so than in the Championship play-off final when he had to play the last 20 minutes without his partner Odoi, who had been sent off. If Ream can rediscover that form, then Fulham’s defensive woes could be over.
A fast start
Ranieri may be the perfect man to take over at Fulham for this very reason. The Italian gets immediate results out of his team due to his incredible man-management abilities. He famously guided Leicester to the Premier League title in 2016 whilst getting the best out of players such as Riyad Mahrez and Jamie Vardy.
The former FIFA Coach of the Year winner used unorthodox tactics to motivate his players, taking them out for pizza if they kept a clean sheet and shouting “Dilly ding, dilly dong” at Mahrez to get him into gear at training.
If Fulham can benefit from this after replacing Jokanovic they could save themselves from relegation as they lie only three points below Southampton in 17th who they face in their next game.
Although Fulham’s recruitment in summer has so far turned out to be disappointing, they did spend in excess of £100 million.
The board could pump even more money in to the squad in January, meaning that Ranieri could look towards some familiar faces to save his new club.
Huth is currently without a club and, with Stuart Gray leaving his post as defensive coach at the start of the season, the Italian could even bring back his former player to fill that vacancy in a player/coach role.
Danny Drinkwater hasn’t played in the league at Chelsea under Maurizio Sarri yet and could be available at a cut price. The Premier League winning manager certainly wouldn’t be averse to signing a key player from his Leicester days.