Jamie Vardy has three times as many bookings as goals in his past 24 Leicester appearances in all competitions

Eight months after celebrating a Premier League title win that ranks among the greatest of all sporting achievements, Leicester find themselves firmly mired in a relegation battle.

Manager Claudio Ranieri this week received a vote of confidence, the club insisting he retains their "unwavering support".

But Leicester's fall has been a dramatic one, leaving them one point and two places above the bottom three.

So what has changed for the champions, and why are things going wrong for a manager who only two months ago was named coach of the year at the Best Fifa Football Awards?

In a BBC Sport poll, 62% of voters think that Leicester will not be relegated this season.

How bad have Leicester been?

It is 79 years since the top-flight title winners have dropped into the second tier 12 months after winning the league, but that is the prospect facing Leicester after the worst title defence ever seen.

The Foxes have yet to win away in the league all season and have started 2017 with a run of five league games without a goal. No other top-flight team has endured such a miserable run since Tottenham, 31 years ago.

It is a staggering contrast to their results in 2015-16, when they lost only three league matches throughout the campaign. In fact, at the start of this season, they had lost only three times in their previous 47 Premier League games.

And don't forget - they did not just win the league last season, they ended up walking it by 10 points.

But since August things have unravelled fast and they have lost 13 out of 24 matches, winning just five times.

What has happened to Jamie Vardy?

Vardy has had different strike partners this season, whereas last year he was predominantly up front alongside Shinji Okazaki

Would you be surprised to find out Jamie Vardy's conversion rate is actually better this season than it was during the title campaign?

Vardy scored 24 Premier League goals in 2015-16, form that saw him named Football Writers' Footballer of the Year and shortlisted for the Ballon d'Or and Fifa's own player of the year award.

This season he has only five league goals, three of which came in one game against Manchester City, and has scored in only one league game since 10 September - a run of 17 matches.

But he is actually more clinical this year.

2015-16 2016-17 Chance conversion rate (%) 22 24 Big chance conversion rate (%) 42 44 Excludes penalties

The problem, it seems, is he is simply not getting the chances. This season, on average, he gets one opportunity every two matches, whereas last season it was more than one per game.

Vardy after 24 games of last season and this season 2015-16 2016-17 Goals 18 (ranked 1st in PL) 5 (21st) Shots (inc blocks) 78 (3rd) 28 (23rd) Shots on target 37 (2nd) 9 (32nd) Chances created (inc assists) 30 (5th) 18 (16th)

While the evidence points to the lack of a supply line (fewer shots, fewer chances), there has also been the suggestion Vardy is not making the runs that proved so successful last season.

Ian Stringer, who covers the Foxes for BBC Radio Leicester, said: "Jamie Vardy haring around is a sight to behold, but it seems rare this season.

"I think that's due to his chances being few and far between; he can't run in behind if he's not being slotted in."

The stats actually show that Vardy is working as hard as last season - covering exactly the same average distance per game - and he is even making more sprints than last year. The ball is simply not finding him when he does. And certainly not in dangerous areas.

2015-16 2016-17 Distance covered per 90 mins (average) 10.1km 10.1km Sprints per 90 min (average) 54.1 57.8

And what about Riyad Mahrez?

Riyad Mahrez's attacking excellence in 2015-16 earned him the PFA Player of the Year award, as well as seeing him named BBC African Footballer of the Year.

That recognition came after a season in which he scored 17 goals and provided assists for a further 11.

This year, his return from 22 matches is three goals - all penalties - and two assists.

So what is he doing differently?

Last season, many of his goals and assists came from trickery and mazy dribbling. This season, he is simply not showing those same skills.

2015-16 2016-17 Mins per big chance created 153 338 Dribble success rate 51% 42% Mins per dribble 12 14 Mins per pass into final third 17.6 19.7

And, of course, there is the collapse of his previously lethal link-up play with Vardy, a combination that led to seven goals last season (ie one player directly assisting the other).

In October, the pair famously went on a run of eight game in which they passed to each other only twice.

That has improved since then - but to no great effect.

In the six Premier League games they have played together since the start of December, Mahrez has found Vardy 16 times (including five times against Manchester United on Sunday).

But it is not leading to goals and, remarkably, the pair have combined for just one goal in the past 12 months.

The Kante factor

It always seemed likely Leicester would lose one, two or maybe all of their three star performers last season.

They kept hold of Vardy after he turned down the chance to move to Arsenal, but the Foxes were powerless to prevent N'Golo Kante leaving for Chelsea for around £30m, as he reportedly external-link had a release clause in his contract.

For a team so reliant on playing on the counter-attack, Kante's ability to break up opposition attacks and protect the back four was a cornerstone of their success.

The Foxes have tried to fill that void, using Daniel Amartey and new signings Nampalys Mendy and Wilfred Ndidi in his central midfield position.

And while Kante has long been noted for his energetic style and ability to cover so much ground, his replacements have more or less matched - and in Mendy's case bettered - his workrate.

But it is Kante's ability to disrupt the opposition's play that they simply have not been able to replace.

As Watford striker Troy Deeney said earlier this season: "You can get through their midfield and get at their back four a little bit easier now.

"Whenever we broke on them last season, I always had the fear factor that Kante was coming back and I knew we didn't have much time before he got there.

"Even if I actually did have time, I always thought he might be there, so I would rush things a bit.

"I always felt Kante did the work of two players."

A rock solid wall that began to crumble

Perhaps the biggest impact of Kante's departure has been on Leicester's defensive solidity.

While last season they kept 15 clean sheets in their 38 games and became notorious for eking out 1-0 wins - they managed seven in total - this term they have been conceding far more regularly and have won 1-0 only once.

2015-16 2016-17 so far Goals conceded per game 0.95 1.7 Clean sheets 15 5 Number of times conceded two or more 11 12 Number of times conceded three or more 1 6

Their backline is an ageing one - centre-backs Wes Morgan and Robert Huth are 33 and 32 respectively - and they are frequently finding themselves exposed.

And it does not help that the team appear to be working less hard as a unit.

"Leicester in recent years have been a team built on effort, going back to their League One days," said Stringer. "All that seems to have disappeared.

"While I'm not questioning the desire or effort, it's the physical exertion which seems less - understandable when you've lost a player like Kante who's dominating the tackles and distances-made charts."

And the stats back up the argument that their workrate has dipped.

They are collectively running an average of 2.1km less per game than they were last season.

2015-16 2016-17 Average team distance run per 90 mins 110.8km 108.7km Premier League ranking for team distance run per 90 mins 7th 14th

The return of the Tinkerman

Leicester used fewer playerslast season - 23 - than any other Premier League team, with Ranieri making a total of 33 changes to his starting line-up over the course of 38 games, the fewest in the division.

This season, with things going wrong from the outset (an opening-day defeat against a Hull side in disarray), the Italian has reverted to being the 'Tinkerman', a nickname picked up while in charge at Chelsea.

There are, of course, mitigating factors. This season, the Foxes have played five more games in all competitions than at the same stage 12 months ago, with Ranieri having to consider the demands of Champions League football on his squad.

He also lost Amartey, Mahrez and Islam Slimani to Africa Cup of Nations duty, making changes inevitable.

But it is not just the players who have changed regularly - Ranieri has also started tinkering with his formation.

The 4-4-2 set-up that brought them so much success last season has been replaced in recent weeks, and Leicester have started with a different formation in each of their past four games.

That has widely been perceived as a failing of Ranieri's, confusing his players and sending mixed messages - the Italian himself conceding they were struggling to adapt after a 3-0 defeat at Southampton in January.

"Maybe my players didn't understand my idea very well," he reflected.

But perhaps Ranieri was actually too slow to identify his side's problems, and too reluctant to move away from 4-4-2.

While many teams adapt their formation depending on the opposition (Tottenham and Manchester City are just two of the sides to have played three at the back against Chelsea's system this season), Ranieri had avoided doing that.

In fact, of the 18 Premier League teams to have used more than one formation in 2016-17 (Arsenal and Liverpool have not altered theirs), Leicester were the last to change.

Which teams were the slowest to try a new formation this season? Team Date of first formation change Matchday of formation change Leicester 31/12/2016 19 Man Utd 06/11/2016 11 Tottenham 01/10/2016 7 Middlesbrough 24/09/2016 6 Chelsea 16/09/2016 5

Ranieri is making up for lost time though. Since his first instance of tinkering - a 1-0 win against West Ham on 31 December - he has yet to choose the same formation in back-to-back fixtures.

So after their dismal start to 2017, will Leicester be able to reproduce the kind of end to the season that saved them in 2014-15, when they recovered from being bottom and seven points adrift with nine games to play?

They are not in quite such serious trouble yet this time around, and Stringer expects them to do enough to stay in the Premier League.

"I think this will be a watershed for them," he says. "Many of the current crop have experience of escaping relegation, and experience of doing it with this team. They'll survive."