Unbeaten filly Fontiton remains a clear-cut favourite to clean sweep the Blue Diamond series after drawing the inside barrier for the $1 million race at Caulfield.

The winner of the fillies' Preview and Prelude, the Robert Smerdon-trained Fontiton is the $2.35 favourite for Saturday's Blue Diamond Stakes (1200m) after coming up with the rails draw in the field of 15.

Jockey Mark Zahra says Fontiton has handled everything thrown at her so far and he has confidence in the filly's ability going into her grand final.

He described barrier one as a reasonable draw for the versatile two-year-old despite admitting he would have preferred a wider gate.

"Barrier one just means we've got to use our spot a bit to hold it," Zahra said.

"You don't want to be getting shuffled back on the fence.

"But she's got a bit of natural speed so she should be right."

Fontiton led and powered clear to win on debut at Moonee Valley in the spring but she has taken a sit in her two wins this campaign.

She galloped with stablemate and Diamond rival Thurlow on Tuesday morning, pleasing Zahra.

"What we have asked of her, she has done every time," he said.

"We've just got one more to go and everything she's done so far points to her not disappointing us."

Pride Of Dubai, a fast-finishing second to Of The Brave in the colts and geldings Prelude, tightened from $6 to $5.50 after drawing barrier five.

His jockey Damian Browne won the race aboard Earthquake last year while his trainer Peter Snowden, now training in partnership with his son Paul, will be chasing his third Blue Diamond having prepared Sepoy and Earthquake for victories during his time as head trainer for Sheikh Mohammed.

Godolphin will have a strong presence in Saturday's renewal with two runners, equal third favourite Sampeah, who has barrier 12, and Bantam who has drawn three.

Both colts will wear blinkers for the first time in the Blue Diamond.

"We were hoping for a middle draw (for Sampeah) but it's certainly not too big a deal," Godolphin's racing manager Jason Walsh said.

"They worked together this morning and worked strongly.

"John thinks the blinkers will be a significant gear change for both horses."