Manchester City face deadline day to appeal against findings that they broke Premier League financial rules, as the Football Association said the case had "implications for the integrity of the game".
The Premier League announced on Tuesday that an independent commission had found the Abu Dhabi-backed club guilty on more than 100 charges.
The likely punishment is uncertain but City, currently top of the world's richest domestic league, could face substantial points deductions, a fine or even expulsion from the top division.
The 10-time English champions, who continue to deny any wrongdoing, have vowed to appeal and had just hours left to do so on Friday.
The English FA broke its silence on the case on Friday, saying that the commission's decision "has significant implications for the integrity of the game".
"We are carefully considering the decision and its implications and will take action where appropriate," the national governing body said in a statement.
"As proceedings between the Premier League and Manchester City Football Club remain ongoing, we do not intend to comment further at this stage. We will, however, continue to monitor developments closely."
The independent commission found that City arranged "sham" deals to artificially inflate revenues and reduce costs by more than £900 million ($1.2 billion) between 2009 and 2018, a period in which they won three Premier League titles and other silverware.
The commission found that the club had concealed the true state of its finances, saying City were "significantly in breach of both the Premier League's and UEFA's spending limits".
NOT ABOVE THE RULES
Downing Street said on Thursday that the super-club was not "above the rules" following criticism of British Prime Minister Andy Burnham over the case.
"As the prime minister made clear, the initial judgement is serious and there can't be any suggestion that anyone is above the rules," a spokesperson said.
Burnham, the former mayor of Greater Manchester, told the BBC on Wednesday that he did not want to see the club's Emirati owners walk away as a result of the case.
"I would be really concerned to lose them," he had said, highlighting the investment the club's controlling Abu Dhabi United Group had made in Manchester.
Oasis star and City fan Liam Gallagher issued an angry post on X on Friday, defending his club.
"All this hatred directed at MAN CITY from other clubs should be directed at ARSENAL, MAN UTD, LIVERPOOL," he said. "(They are) the ones who are corrupt and trying to stop other teams from winning things not MAN CITY."
Everton and Nottingham Forest were given points deductions in the 2023/24 season for single breaches of financial sustainability rules.
On that basis, City could face relegation given the sheer scale of the case.
There is speculation that they could even be stripped of their titles.
UAE airline Etihad Airways, City's main sponsor, said that it was considering legal action against the Premier League.
"Etihad categorically rejects any finding, conclusion or implication that suggests the airline has ever been involved in improper commercial arrangements," an Etihad spokesperson said in a statement.
The airline said it was "deeply concerned" by how the matter was communicated to the public, referring to "selective leaks and reporting".
Another factor is a potential flood of compensation claims. Former Liverpool managing director Christian Purslow told the BBC that clubs would be "queueing up to seek compensation".
City have become the Premier League's dominant force since the 2008 takeover by Sheikh Mansour, the vice-president and deputy prime minister of the United Arab Emirates.
The team are next in action against Liverpool at Anfield on October 11, where they will take on the club who have been their closest challengers for much of the past decade.