What's gone wrong for Chelsea in the WSL this season?

Chelsea have gone from winning everything domestically without losing a game to falling 12 points adrift of the Women's Super League leaders - all within the space of nine months.

The dominant force in England for almost a decade, Chelsea were attempting to clinch a seventh WSL title this season but find themselves in a battle to retain a qualification spot for next season's Women's Champions League.

The drop-off? Unimaginable. Their most recent 5-1 defeat by Manchester City on Sunday? A humiliation.

Afterwards, boss Sonia Bompastor pledged to keep searching for solutions but conceded she would be "happy" to leave if the Chelsea hierarchy felt her time was up.

So where has it all gone wrong for her side this season?

The obvious sign that things are not as harmonious is the results.

Last season, Chelsea dropped just six points. A shock defeat by Everton, a surprising draw with Liverpool, and now back-to-back losses - for the first time in 11 years - to their rivals Arsenal and Manchester City, means they have already thrown away 15 points by 1 February in this campaign.

But Chelsea's problems felt bigger on Sunday when, for perhaps the first time in her tenure, manager Bompastor dropped subtle hints of internal frustration.

She repeatedly highlighted the squad's lack of depth, insisting it was not what it was last season, and touched on how that limited her ability to switch things up tactically, or to rotate players to keep them fresh.

Pressed on whether she had wanted more from their summer recruitment, Bompastor smiled and simply said: "Without making too many comments on that, I would have liked to have been in a better place from the last transfer window."

Of their five signings from the summer, only Ellie Carpenter and Alyssa Thompson are starters. They broke their club record fee to bring in Thompson for almost £1m, and spent money on Carpenter too, but Bompastor wanted more.

Injuries to key players such as Mayra Ramirez, Nathalie Bjorn and Lauren James, have harmed them in defence and up front in patches this season.

And with the January transfer window closing on Tuesday and no incomings yet, Bompastor is clearly aggrieved.

WSL leaders Manchester City made a statement signing in American midfielder Sam Coffey in this window, while Arsenal are already lining up huge pre-contract agreements for Spain full-back Ona Batlle and England international Georgia Stanway to arrive in the summer.

"A lot of people talk about Chelsea being an example of having depth in the squad and of having players with different profiles they can bring into the game. Right now, I don't think we are in that place," said Bompastor on Sunday.

"I'm not saying that explains everything, but being in that position probably doesn't help. As a manager I will always [accept responsibility for] the results of this team so I need to focus also on what the solutions are for me to be in a much better place.

"It's tough because I have to focus on the players available but when you have many games in a row, you can't rotate as much as you want and you can't bring in the exact profile you want in the game."

While Bompastor's frustrations may carry some weight, there are also concerning trends in their performances.

A squad still packed full of talent and experience has looked bereft of ideas and lacking ruthlessness.

The 'mentality monsters' of recent seasons are no longer perceived to be invincible as they look more vulnerable defensively and less clinical up front.

According to Opta, they are underperforming their expected goals tally by more than any other team (24 scored from 29 expected) and in their 2-0 defeat by Arsenal, they had 18 shots but only one on target.

This is the first WSL campaign in which Chelsea have recorded one or fewer shots on target in multiple games (also against Liverpool in their 1-1 draw).

They had 70% possession in the opening 15 minutes of the second half against Manchester City on Sunday - but their opponents scored twice in that period.

And that 5-1 defeat was the joint-biggest they have suffered in the WSL, placing them the furthest from the top of the table they have been since the final day of the 2018-19 season.

"It was two top teams playing against each other and one was efficient and the other was not. I'm not putting everything on the players, but we made too many mistakes and we need to solve that," said Bompastor on Sunday.

"I always reflect on my own decisions and my tactics. I'm always hard on myself. We played the game against Arsenal with a back three. This game, we changed the system to a back four and tried something different with different players.

"As much as you always want to explain things in football, sometimes it doesn't work. When it's like this, it's tough for sure.

"You need to find the solutions, stay strong, and make sure we work on the basics. We need to get back to a level where we are producing more."

It was a rare sight to see Chelsea's players look so dejected and they appeared to fall apart in a second half at Etihad Stadium in which City toyed with them.

Bompastor said she was not concerned, but with fans increasingly questioning her tactics and the players looking short of confidence, does she remain convinced she is the right person for the job?

"In the club, if people think I'm not the right person to stay in this job, then I'll be happy to go if they think that's the right thing," she said. "But I will never give up.

"In football, I know sometimes it happens and you can be in this situation. I will always fight but the institution at Chelsea is a lot more important than myself."

It seems absurd to question a manager who led the club to an unbeaten domestic treble in her debut season but such are the high expectations at Chelsea.

With a place in the Women's League Cup final already booked, a Women's Champions League quarter-final on the horizon and their Women's FA Cup campaign still on course, it is not yet a crisis at Chelsea.

But with their WSL title defence all but over, there will undoubtedly be sharper focus on those knockout competitions.

Ben Haines, Ellen White and Jen Beattie are back for another season of the Women's Football Weekly podcast. New episodes drop every Tuesday on BBC Sounds, plus find interviews and extra content from the Women's Super League and beyond on the Women's Football Weekly feed