Trainer Paul Beshara has been charged with treating Happy Trails before the Group One winner was due to run in the Dato Tan Chin Nam Stakes.

Racing Victoria stewards ordered the scratching of Happy Trails from last Saturday's Group Two race at Moonee Valley after a report from the Compliance Assurance Team (CAT).

The CAT inspected the horse at 9am (AEST) and when they returned about two hours later discovered a hematoma on the horse's neck and some blood.

The vet who inspected the horse gave evidence that it was consistent with a recent injection.

Beshara said Happy Trails had been treated during the week but denied the horse had received any medication on race day.

The horse is entered for Saturday's Group One Underwood Stakes.

No date has been set for the hearing.