Manchester City are in uncharted territory under Pep Guardiola.

A 1-0 loss at Nottingham Forest condemned the Premier League champions to their ninth league defeat of the campaign - equalling their record for most league defeats in a season during the Spaniard's reign.

And for the first time under Guardiola, qualification for the Champions League is under serious threat.

It is a scenario that was unthinkable as City lifted their fourth consecutive league title last May.

Though a fifth-placed finish could yet provide a Champions League lifeline, there are just five points between fourth-placed City and Fulham in 10th as we enter the final stage of the season.

Manchester City have not missed out on Champions League qualification since the 2009-10 season.

They have qualified for the tournament with relative ease in seven of Guardiola's eight full seasons at Etihad Stadium.

The only exception came during Guardiola's first season in England, when City sealed Champions League qualification on the final day of the 2016-17 season by finishing third.

City's run of form does not make for happy reading.

Speaking to TNT Sports, former Everton and Swansea defender Ashley Williams summed up the unprecedented position City find themselves in.

"We are so used to seeing Man City be exceptional that a season like this is considered a crisis," said Williams.

Former City defender Joleon Lescott said it would be a "disaster" if City failed to qualify for the Champions League.

"City are in control of their fate. It would be disastrous if they didn't qualify for the top four," said Lescott

City have 10 matches remaining in their Premier League season.

Guardiola says he side must treat every single game as a "final", starting with the visit of Brighton, who are just one point behind City, to the Etihad next Saturday.

"We have 10 games to qualify," Guardiola said.

"We have to win games to qualify and we move on to the next one.

"Every season the Premier League gets better and better. We have 10 finals [to come].

"We don't win enough games in a row to be secure. We have to do something, it doesn't come from the sky."

City spent more than £180m in the January transfer window, bringing in the likes of Nico Gonzalez and Omar Marmoush.

But the side's form has remained inconsistent, with City winning four and losing five of their nine matches since the close of the window.

Former Manchester United captain Rio Ferdinand feels the January signings are suffering from the team's instability.

"I don't think they brought in bad players but they have just come in in less stable times," Ferdinand told TNT Sports.

"You can't bet against Man City, they have the players and the manager."

Former England centre-back Lescott says City must qualify for the Champions League in order to attract the best players this summer.

"If you want top, top players, Man City need Champions League football," Lescott told TNT Sports.

"Elite players need Champions League football."

A failure to qualify for the Champions League would also damage the club's finances.

City earned about £90m as they went out of the Champions League at the quarter-finals stage last season.

Their play-off exit to Real Madrid this season means they stand to earn about £28m less, with an estimated £64m windfall this time.

But failure to qualify for the competition for next season would be far more costly.

Rivals Manchester United recently announced their quarterly results for the three months ending 2024.

Revenue was down 12% - a fall of over £25m - after the club failed to qualify for the Champions League and entered the Europa League instead.

Over the course of a year, the cost of being outside the Champions League can cost clubs about £100m in lost revenue.