Respected Victorian trainer David Brideoake has been cleared of race day treatment with Racing NSW stewards determining the charges could not be proven.

The Brideoake-trained Princess Jenni was a late scratching from the Adrian Knox Stakes at Randwick on April 6 when she was found to have a small lump on her neck, consistent with an injection.

After taking evidence at a hearing in Sydney on Monday, stewards found the lump could have been caused by exposed steel mesh on her stable door or from a routine injection two days earlier.

Swabs taken from the filly showed nothing untoward.

After missing the Group Three Adrian Knox, Princess Jenni was taken back to Victoria where she won at Flemington two weeks later.

She went on to win the Group One Schweppes Oaks at Morphettville another two weeks later as favourite.

The panel headed by chief steward Marc Van Gestel, said they could not be comfortably satisfied to the required standard of proof, Brideoake had injected or caused Princess Jenni to be injected against the rules,

"Accordingly, the stewards find the charges issued against Mr Brideoake are not proven," the stewards report said.

Stewards also took into account Brideoake's good reputation in the industry and his clean record.