Unlike most Australian horses who are gelded before racing in Hong Kong, Thunder Fantasy has returned home with a view to enhancing his stud career.

Under his then trainer Anthony Cummings, Thunder Fantasy racked up three Group One placings in Australia and claimed a domestic Group One win in the Hong Kong Classic Cup for John Size.

The six-year-old is back with Cummings at Randwick where he races in Saturday's 1400m-open handicap carrying 63kg.

"He had some issues over there and was retired from racing in Hong Kong," Cummings said.

"He came home and was doing too well in the paddock so we decided to put him back in work.

"He's come good and we'll see how good when he goes to the races."

Thunder Fantasy ran third in the 2013 Victoria Derby won by Polanski and the following autumn was third in the Australian Guineas behind Shamus Award and Criterion and second to Criterion in the Australian Derby.

His Hong Kong Group One win was over 2000 metres in February 2015.

When the decision was made to get him racing again, Cummings entered him for the Cox Plate and although that will be too soon, the trainer is not shying away from the top level.

"He won't be ready for the Cox Plate but there's a mile race on Derby day at Flemington that could suit," Cummings said.

The Group One Longines Mile is the race formerly known as the Emirates Stakes.

Thunder Fantasy will be ridden by Tye Angland on Saturday with Cummings not tempted to use a claiming apprentice despite the horse's big weight.

Cummings has given Thunder Fantasy three barrier trials in the past month to get him ready for his first race since May last year.

"He is well performed and well-travelled so hopefully there is a stud out there for him," Cummings said.