Blake Shinn's hopes of a first Cox Plate have been thwarted by a careless riding suspension out of the Seymour Cup in country Victoria.

The jockey was outed for eight meetings for causing interference to two other runners in the early stages of Sunday's race won by Turn Me Loose from the stable of Caulfield Cup winning trainer Murray Baker.

Shinn, who rode the unplaced Madam Gangster at Seymour, will miss the ride on either Preferment or Winx in Saturday's Cox Plate with Hugh Bowman getting first choice of the Chris Waller-trained pair.

Champions Day at Ascot has also been costly for last year's Cox Plate and Melbourne Cup winning rider Ryan Moore and Singapore-based Australian Corey Brown.

Moore was outed for four meetings which include Melbourne Cup day.

Under British rules he can apply to have the ban deferred for Group One days and is likely to do so to at least ride at the Breeders' Cup meeting in Kentucky on October 31.

Moore won the 2014 Cox Plate on the Aidan O'Brien-trained Adelaide and Melbourne Cup on Protectionist.

Brown, winner of the 2009 Melbourne Cup on Shocking, was in England to ride Singapore's Emperor Max in the Champions Sprint won by Muhaarar.

The Stephen Gray-trained Emperor Max finished seventh with Brown outed for two days, October 31 and November 3.