Manchester City were the ultra-rich "noisy neighbours" who became the Premier League's dominant force. But they now face an uncertain future that includes the ultimate threat of relegation.Abu Dhabi-backed City were charged by the English top flight on Monday with more than 100 alleged breaches of financial rules between 2009/10 and 2017/18 and referred to an independent commission.The reigning champions have also been accused of failing to cooperate with investigations by the Premier League.The club faces a range of possible punishments, including a reprimand, points deduction or even expulsion from the Premier League.City, who last month topped the Deloitte money league of the world's richest clubs, appear to be confident they can ride out the storm, insisting there is "irrefutable" evidence that supports their case.It is not the first time the club, transformed on and off the pitch after its takeover by the Abu Dhabi United Group in 2008, have been in the spotlight over issues of finance.City were fined 60 million euros ($64 million) in 2014 for breaching UEFA's Financial Fair Play regulations.The club were banned for two years from UEFA competitions in February 2020 by European football's governing body for "serious financial fair play breaches", but the sanction was overturned by the Court of Arbitration for Sport later that year.Last year City manager Pep Guardiola made it clear that he would walk away from the club if he discovered he had been lied to by the club's owners -- a worst-case scenario for City, who have won four of the past five Premier League titles under his leadership.The Times' chief football writer Henry Winter said City faced "allegations of wrongdoing on an industrial scale...If proved, the