It’s not just that Leicester City were doing the same thing over and over again and expecting a different result, they were doing the same thing over and over again and getting worse.

Ruud van Nistelrooy needed to try something different to break the monotony of City’s form and to inject even a slight sense of hope back into the club and the fanbase.

And he did. Frankly, it was a surprise. Everything van Nistelrooy has said during his first few months in charge suggested he was stubbornly committed to 4-2-3-1 as the undeniably best formation and wasn’t going to deviate from it.

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That’s especially not to a back five, given the only other time City played in that system this term was at Brentford when van Nistelrooy was in the stands to watch a calamitous display.

But spooked by what he has now described as the “alarming” display against West Ham, with the result at Tottenham and decent performances against Manchester City and Crystal Palace becoming an ever-distant memory, van Nistelrooy took the initiative.

With 10 days to work with his side, the longest gap he’s had between fixtures since his debut in early December, he had time on the training ground for his team to get to grips with it too.

Did it work? Well, City lost again and didn’t score again, and so there will be plenty whose instincts suggest the new tactics were not enough to change the same old story.

But van Nistelrooy was very happy, and said he “couldn’t have expected it to go so well” after just one week of work.

By the very low bar set by the West Ham defeat, it was an improvement. The system, perhaps because the players were more compact, did generate a greater sense of togetherness. There was a far greater sense of the fighting spirit required to succeed in a relegation battle.

Defensively, it was better too. Despite City giving up plenty of territory and conceding 19 shots, clear-cut chances for Chelsea were limited.

In fact, in terms of non-penalty expected goals, Chelsea’s tally of 0.8 was the joint-lowest in a game against City, level with van Nistelrooy’s Manchester United against Steve Cooper’s City back in November.

It meant that, come the final few minutes, City were still in the game. Too often recently there have been fixtures where the final stages of matches are soul-draining experiences with the result a foregone conclusion, the City players visibly lacking in belief that a comeback is possible.

At Stamford Bridge, City at least defended well enough that they gave themselves a chance. A lucky bounce here or there and they’d have come home with a point.

The shape deployed by van Nistelrooy is very similar to that with which City won the FA Cup and also masterminded their great escape from relegation 10 years ago.

It feels very unlikely that City will overcome the six-point gap to safety this time, but it felt that way a decade ago too when seven points needed to be clawed back.

Perhaps this new formation is the key to City’s revival. It certainly seems like van Nistelrooy is now invested in it and will continue to play that way.

It at least gives City a semblance of optimism to cling to. It also shows van Nistelrooy has not given up the fight and is willing to look beyond his usual game plans to try to find a solution to City’s woes.

What RvN still didn't get right

But to be clear, the change in formation was not wholly positive. Van Nistelrooy said his side “deserved more” but that’s a difficult take to agree with when it was perhaps City’s least threatening performance of the season.

They had three shots, the fewest they’ve mustered in a game all season, and they managed an expected goals tally of just 0.1. They had four touches in the Chelsea box, the joint-fewest they’ve had in a match this term.

In the half-hour they were chasing an equaliser, they had one effort at goal, and that came after they dispensed with the five-at-the-back system.

Van Nistelrooy said the new shape helped get more support around Jamie Vardy but that did not seem to be true.

There were several moments where Vardy received the ball near the halfway line or just beyond and had to hold up play for what felt like an age until the support arrived.

If van Nistelrooy is now going to persist with this shape, then attacking tweaks are needed. Patson Daka is perhaps the man who should make way.

He didn’t perform badly and for a good while it was his combination play with Wilfred Ndidi and James Justin on the right-hand side that looked like City’s most dangerous route of attack.

But he didn’t play as a striker. He kept dropping deep to receive the ball and offload it and was rarely in the box when City did then advance the ball. There was no real partnership with Vardy.

Off the ball, he was diligent in getting back to defend on the right wing. But it meant, when City were breaking out and he was in that position, it didn’t look comfortable for him.

If City are going to make this work, they need to swap him out for an attacking midfielder, someone more suited to playing in between the lines and connecting play.

Facundo Buonanotte would be the obvious choice, allowing him to develop a partnership with Bilal El Khannouss again, but Jordan Ayew may be a better bet too as someone to receive the ball and hold it up.

Full-backs given chance to succeed

It’s rare that van Nistelrooy singles out a player without prompting but he did just that for Luke Thomas on what was just the academy graduate’s second league start under the Dutchman.

He delivered what the manager wanted in terms of defensive security. After a wobbly first few minutes, Thomas settled and only Wilfred Ndidi made more tackles, while no player made more clearances.

He guarded the penalty area stoutly but also pressed out effectively too, following his man into midfield to put the pressure on.

It feels like he will be preferred in this system, on the left of the central defensive three, over a traditional centre-back like Caleb Okoli or Jannik Vestergaard.

He’s naturally left-footed, which helps his cause, while he’s usually accurate with his short passing, more so than he was against Chelsea.

City’s full-backs have come in for plenty of criticism this season, but the roles the new system gives them feels more suited to their qualities.

James Justin and Victor Kristiansen, and likely Woyo Coulibaly, feel more comfortable as wing-backs, where their stamina and willingness to get forward can be put to better use, and where there’s more cover for them in behind.

Justin in particular had a very good game, darting in behind Marc Cucurella to give City a good option wide right, while also getting back to defend the far post well.

Kristiansen was not at his best but it’s the role he plays with Denmark and so it’s not something he was unaccustomed to.

None of Thomas, Justin nor Kristiansen had perfect games but if this is the way forward, it feels like all three are being put in a position to better succeed.

Ricardo return and late-game change

The fourth full-back who featured on the day was Ricardo Pereira, the Portuguese a welcome sight off the bench as he made his first appearance in four months.

Given his lengthy absence and given his long list of injury problems, he did not look at all rusty, and both of City’s best two chances for a late goal came through him.

First, he found space in the pocket to dribble at goal and get a shot away, and then he found a yard of space to the right of the box to cross in dangerously, the ball just behind Buonanotte.

If he can stay fit, there are lots of benefits to having Ricardo back available. His technical, tactical and attacking abilities rank above those of many of his team-mates.

But he also allows City to try yet another formation. Because when he came on as part of a triple substitution, van Nistelrooy dispensed with the back five and opted for the inverted full-back system from last season.

With Harry Winks on the pitch already, City immediately got back into their stride, and it was from there that they created the two moments for Ricardo.

The opposition do enough preparation that it won’t go unnoticed and it won’t be the case that managers will be surprised if City change formations midway through a game.

But dealing with it is another matter. Even against Enzo Maresca, the man who City learned the system from, they had joy once they changed shape for the final few minutes because Chelsea were not quick enough to adjust.

City haven’t just come away with one new system, but two, and using both in the same game depending on the circumstances could be beneficial.

Man Utd showdown 'must-win'

However, time is running out. It’s another weekend in which City have seen 17th place move further from their reach.

But the weekend where Wolves drew with Everton and City lost to Chelsea is not going to stand out in the post-season post-mortems as being decisive. Next weekend might be.

Wolves travel to Southampton, a fixture they will expect to win, even without top scorer and star man Matheus Cunha.

City host Manchester United, van Nistelrooy’s old club. Despite losing to United three times already this season, it looks to be one of the most winnable games in City’s run-in. They’re in the bottom half for a reason.

Because if the results at St Mary’s and the King Power Stadium see the distance between Wolves and City grow at the weekend, it will be extremely difficult to foresee an escape.

City can’t return from the March international break, when they have a run of fixtures against Man City, Newcastle, Brighton and Liverpool, sitting more than six points from safety.

If Wolves defeat Southampton on Saturday, the Manchester United fixture feels like it would become a must-win.

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