Gai Waterhouse has hit out at Racing NSW stewards claiming there is a bias against her after being called to another inquiry regarding the condition of one of her horses.

No charges were laid against the trainer at Friday's inquiry but she was reminded of her obligation to inform stewards if there were any issues that could affect a horse's performance in a race.

The latest incident unfolded on Wednesday when stewards acted on reports Rockabill had been lame in the lead-up to Wednesday's Group Three Spring Stakes at Newcastle.

The colt was inspected at Waterhouse's Randwick stable on race morning by Racing NSW chief veterinarian Dr Craig Suann who found him to be lame and said he could not race.

Waterhouse said she had been in Melbourne and wanted to inspect the horse on her return before she reported any injury.

At the beginning of the inquiry, Waterhouse's counsel Philip Beazley, failed in his application to have chief steward Ray Murrihy and deputy chief steward Marc Van Gestel removed from the panel hearing the matter due to perceived bias.

He also failed to get permission for the inquiry to be adjourned in order for Waterhouse to seek a Supreme Court injunction to prevent the panel from hearing the case.

Van Gestel, who provided a statement to the inquiry regarding communications on the morning of September 18, stood himself down from the hearing.

The latest case comes on top of fines issued to the trainer earlier this year at the conclusion of the high-profile More Joyous inquiry.

Waterhouse was penalised $5000 for failing to report a condition that could affect More Joyous' performance in the All Aged Stakes and another $2000 for a similar offence relating to the mare before the Queen Of The Turf Stakes.

Murrihy reminded Waterhouse on Friday of her responsibility to report any problems with a horse as soon as practical and that her absence from the stable should not delay the process.