At the time of making entry, the owner, trainer or authorized agent shall designate a jockey only if the jockey named is definitely engaged. If the jockey is not definitely engaged, then an entry shall be made without designating the jockey at the time of entry. Change of jockey designated may be made only by authorization of the stewards. Any violation of this rule will subject violators to fine or suspension.
Ill. Admin. Code tit. 11, § 1413.120