CNN  — 

What started with claims in a German magazine has resulted in Manchester City being banned from European club competitions for two seasons and fined $32.5 million.

UEFA’s decision to punish the reigning English Premier League champion after it found the club had committed “serious breaches” of the European governing body’s club licensing and financial fair play regulations has led to shock, denial and plenty of questions.

The punishment is subject to appeal to the Court of Arbitration for Sport, and City immediately issued a statement Friday describing UEFA’s process as “flawed” and making it clear the fight is not over.

But how did it come to this and what now for one of the world’s richest football clubs and its manager Pep Guardiola?

In November 2018, German magazine Der Spiegel reported that City and its sponsors manipulated contracts to circumvent UEFA’s Financial Fair Play (FFP) rules, introduced in 2011 to stop clubs overspending.

Leaked emails obtained by Der Spiegel from the Football Leaks organization suggested City’s Abu Dhabi owners had paid the club directly rather than Etihad, which is the club’s shirt sponsor and has naming rights for its stadium. Der Spiegel, citing club documents, alleged the airline financed only part of the sponsorship deal, with the owners coming up with the rest.

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Guardiola's current contract with Man City ends in 2021.

FFP rules state clubs can only lose $32 million over three seasons otherwise they will be liable to a fine or suspension.

Last March UEFA began its investigation and in May the case was referred to UEFA’s financial watchdog, the financial control body adjudicatory chamber (CFCB), with City filing an appeal to CAS in June, which was rejected in November 2019.

On Friday, CFCB said City had broken the rules and, significantly, “failed to cooperate in the investigation.” In its statement, City said the emails had been taken out of context and the case had been “initiated by UEFA, prosecuted by UEFA and judged by UEFA.”

In the immediate aftermath, the future of Guardiola, widely regarded as the finest manager of his era, has been the main focus.

The former Barcelona and Bayern Munich coach has previously maintained he would remain at City at least until his contract expires in 2021.

Under Guardiola’s leadership, City has broken records and played mesmerizing football.

Man City has won back-to-back league titles.

In winning the EPL in 2017-18, City became the first English club to record a 100-point haul. And in successfully defending the league title and securing the FA Cup and League Cup last season, the club became the first to win all three domestic trophies in a single campaign.

But in his four years in Manchester, one trophy has eluded him, which was the main reason he was brought to the club – the Champions League, the richest competition in European football.

Only last week Guardiola talked of how he might be sacked if he does not win European football’s top prize soon. That statement may have been overdramatic, but if UEFA’s decision is upheld, Guardiola needs to win the Champions League this season or likely face never winning the trophy he covets the most with City.

Will Guardiola be happy to wait until 2023 to restart his Champions League quest with City? By the end of his present contract, he will have stayed at City longer than at any of his previous clubs. And with unprecedented heights already scaled on the domestic front, many are asking what would motivate him to stay.

Could this be the end of an era for Manchester City?

Even before Friday’s seismic punishment, it had become clear City would have to rebuild in the summer.

With Liverpool currently 22 points ahead of City in the league, the club needs an injection of players if it is to reclaim its position as the dominant team in England.

Veteran midfielder David Silva is to leave at the end of the season. It is uncertain whether striker Sergio Aguero, City’s all-time leading scorer, will remain beyond his current deal, which ends in 2021. Young forward Leroy Sane is also being heavily linked with a move to Bayern Munich.

If Guardiola leaves, so could a number of other stars. Raheem Sterling and Kevin de Bruyne are in long-term deals, but they will want to test themselves against the best.

With rich owners, money is not a problem for City – but without the prestige of Champions League football, will City still be able to attract elite players? UEFA’s punishment has shaken City. It could also lead to an end of an era.