Pep Guardiola has called on the Premier League to loosen its rules on emergency signings outside the transfer window amid Manchester City's current goalkeeping crisis.
Claudio Bravo faces a lengthy spell on the sidelines after injuring his Achilles tendon in training on Tuesday, leaving the Citizens short of cover for first-choice stopper Ederson.
Montenegrin youngster Aro Muric has been recalled from a season's loan at Dutch side NAC Breda to act as second choice, with youth graduate Daniel Grimshaw the other senior keeper in the squad.
With the Premier League champions unable to recruit a goalkeeper registered with another club until January, they were left with the option of signing a free agent.
However, Man City would still have needed permission from the Premier League to register a free agent to play, and there is no guarantee that it would have been given.
When asked by The Telegraph about whether the rules need to be reviewed, Guardiola replied: "Yes. Not just for goalkeepers but for when there are big injuries to players. If we had not been allowed to bring back Aro, I don't know what would have happened.
"But the rules are the rules. Maybe the federation can think about that when there are long injuries and it is still the period where the European window is open. Then maybe you could do it.
"Here it is closed, and it is good that the competition starts with the whole squad [in place]. But maybe we could think about that, especially when the injuries are five or six months."
City, who have been linked with former Liverpool and Crystal Palace stopper Diego Cavaleri in the past few days. allowed Joe Hart to join Burnley earlier this month having already sold Angus Gunn to Southampton.
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