Green Moon and Silent Achiever have joined the list of this season's high profile retirees.

The 2012 Melbourne Cup winner for Lloyd Williams and his family, Green Moon finished last in Saturday's Doomben Cup in which New Zealand mare Silent Achiever was 10th of the 15 runners.

Green Moon beat Fiorente to win the Melbourne Cup with the runner-up successful a year later.

The pair met again in the 2014 Australian Cup with Green Moon second to his rival in his best performance since the Melbourne Cup.

Nick Williams praised Green Moon on Twitter when he announced he had run his last race.

"Not sure we have ever owned a horse that tried so hard, today he said enough," Williams said.

An eight-year-old entire by Montjeu, Green Moon retires with seven win from 36 starts and almost $5.4 million prize money.

Silent Achiever, the winner of the 2012 NZ Derby, enjoyed her finest campaign in the autumn of 2014 with three successive Group One wins.

She followed her NZ Stakes win with victories in the Ranvet and BMW during the Sydney autumn.

Trainer Roger James has been behind this eight-ball this autumn with the mare failing to win in six starts.

James and owner Kevin Hickman plan to send her to Europe where she will be served to southern hemisphere time by a prominent stallion.

By the late O'Reilly out of Zabeel mare Winning Spree, Silent Achiever goes out with 10 wins from 36 starts and earnings of more than $3.6 million.

Among this season's Group One winners to bow out are Dissident, Hallowed Crown, Sacred Falls, Shooting To Win and Adelaide who are all headed to stud.

Wandjina and Brazen Beau will also go to stud in the spring after they compete at Royal Ascot.