Champion jockey Damien Oliver will test the Blue Diamond Stakes credentials of Real Saga when the exciting Sydney colt makes his much anticipated Melbourne debut.

Unbeaten in two starts, Real Saga is one of the favourites for the Blue Diamond (1200m) on February 21 and is among 18 nominations for Saturday's Group Three Blue Diamond Stakes Prelude (1100m) for colts and geldings.

Co-trainer Wayne Hawkes said the son of Tale Of the Cat hadn't been put under pressure at his two runs and booked his ticket to Melbourne after beating four others when resuming at Randwick on January 24.

He won the Breeders Stakes at his only other start at Randwick in October last year.

"He has never really been extended yet but on Saturday will give us a guide where he is at," Hawkes said.

"He couldn't do anymore than what's he's done but we will see what he is about when he goes head and head with another horse."

TAB Sportsbet has Real Saga and last Saturday's Talindert Stakes winner Come Hither, trained by Lee Freedman, Blue Diamond equal second favourites at $7.50.

Unbeaten Steve Richards-trained filly Rostova dominates the market at $3.50 but could end up even shorter should she win Saturday's fillies Blue Diamond Prelude (1100m) at Caulfield.

She has posted easy stakes wins at her only two starts, including the Blue Diamond Preview by 2-1/2 lengths at Caulfield on January 26.

Rostova looks set for a showdown with other unbeaten fillies Exceedingly French, trained by Freedman, and Quick Blush, trained by David Hayes.

All three fillies have raced twice but Rostova is yet to race beyond 1000 metres. Exceedingly French has won at 1200 metres and Quick Blush is successful up to 1100 metres.

Peter Moody-trained Reward For Effort, who won the colts and geldings Blue Diamond Preview at his only start, is nominated for Saturday's Prelude along with preview third placegetter Bombay Sling.

Moody has also entered first starters Doubtful Jack ($100,000 Magic Millions yearling), Senor Zorro ($170,000 Magic Millions yearling) and Seventh Heart who wasn't offered at the sales.

Shoot Through, a $2.2 million brother to outstanding sprinter Alinghi, and The Comedian, who cost $1.7 million, are both scheduled to make their debuts in the colts and geldings prelude.

Mick Price trains Shoot Through for Nathan Tinkler's Patinack Farm and he is $31 for the Blue Diamond while The Comedian is Freedman's only entry in Saturday's event and $41 to win the Diamond.