Katelyn Mallyon has failed in her appeal against a careless riding suspension and will miss the ride on Super Cash in the Group One Newmarket Handicap.
Apprentice Ben Allen has picked up the ride on the last-start Rubiton Stakes winner in Saturday's 1200m sprint at Flemington and rode the mare in trackwork on Tuesday morning.
Mallyon was given 12-meeting ban at Flemington on Saturday and her appeal was heard on Tuesday.