Australian Cup-winning jockey Michael Walker has failed in his appeal against the severity of an eight-meeting suspension.
The Australian Cup-winning jockey was suspended on a careless riding charge at Flemington last Saturday.
The ban stemmed from his winning ride on Wawail in the Kewney Stakes.
Walker had pleaded guilty to the charge and was looking to have one day shaved off the penalty to allow him to ride Criterion in the George Ryder Stakes at Rosehill on Saturday.
Craig Williams will now ride Criterion.