Apprentice Katelyn Mallyon has revealed she will be out of the saddle for four to six weeks because of an ankle injury suffered in a mishap at trackwork.

Mallyon was cleared of a broken ankle after being taken to hospital after the accident on Tuesday, but underwent an MRI scan the following day to determine the extent of soft tissue damage.

The apprentice said on Twitter she would require a stint on the sidelines but did not need surgery.

"Disappointing news to be out 4-6 weeks in a moon boot but thankful to not have surgery!" Mallyon tweeted.

Mallyon was on a horse walking through the tunnel at Caulfield racecourse when it took fright at another horse.

The apprentice came off and the horse then stood on her ankle.

Mallyon's apprenticeship is due to finish at the end of August but she is expected to apply for an extension to enable her to ride the two winners she needs to lose her claim.