On a stellar day for trainer Peter Moody, stud-bound Dissident has strengthened his hold on the Horse of the Year title with victory at his final start in the Group One All Aged Stakes.

Moody came to Randwick on Saturday for the final day of the carnival with three runners, and made a clean sweep with Pasadena Girl taking the other Group One race, the Champagne Stakes, and Hi World the Frank Packer Plate.

Dissident's fourth Group One win of the season coincided with his reunion with Jim Cassidy who had not been aboard since the Randwick Guineas in March last year.

Wearing a black armband to honour his sister-in-law Marion who died earlier in the week, Cassidy kept Dissident ($10) in touch with the leader Wandjina ($7.50) and edged past him to win by a head.

"The black armband got me home," Cassidy said.

"Vic lost her sister on Wednesday and that one's for Marion.

"I said to her before I left 'if anyone can win on him darling I will for Marion'.

"I even left a letter at home with a love heart and I said `I'll do this one for Mazza bub'."

It was the 104th Group One victory for the 52-year-old whose 103rd came a week ago in the Sydney Cup.

Dissident won the Memsie Stakes (1400m) and Makybe Diva Stakes (1600m) in the spring and the CF Orr Stakes in February over the 1400m of the All Aged.

"He has never gotten the accolades he deserves.

"He has raced at Group level from day one and won five Group Ones.

"He won his first start and he's won his last start.

"I've had the pleasure of retiring three Group One winners - Typhoon Tracy, Black Caviar and Dissident.

"The first two were Horse Of The Year winners. This bloke has put his hand up to be number three."

Chautauqua, who gained an overdue Group One win in the TJ Smith Stakes two weeks ago, finished third as the $3 favourite, a long neck behind Wandjina.

Moody said he had come to the races confident he had three good chances.

"I thought we had three great hopes but you can never be too confident," he said.

Henry Field, the proprietor of Newgate Farm where Dissident will stand in the spring, said it was Moody's confidence in the horse which convinced his new owners to give him an autumn campaign after he had a bleeding attack in the Caulfield Stakes.

"Peter just filled me with such confidence," Field said.

"When I went to buy him he just said this horse is the elite of the elite.

"He said if you keep him in training, he will be Horse of the Year."

Dissident is the only horse to win four Group One races in 2014/15 with the Adelaide and Brisbane carnivals the last chances for any to stake their claims.

Lucky Hussler was demoted from fourth equal in the All Aged to sixth after deputy chief steward Greg Rudolph fired in a successful protest on behalf of Generalife's rider James McDonald for interference in the straight.

Scissor Kick gained outright fourth with Generalife promoted to fifth.