Ronaldo's treble was the 51st in World Cup history and saw him become just the fourth player to score at four different editions of the tournament.
The Foxes' appeal to FIFA to secure the registration of Silva was last week rejected by world football's governing body.
The appeal was rejected despite FA support as the paperwork was submitted 14 seconds late on deadline day.
Portugal midfielder Adrien Silva has been unable to train and remains in limbo as Leicester City bid to sort out his future.
Leicester City agreed a 24 million euros deal with Sporting Lisbon for the 28-year-old Adrien Silva on August 31.