Unbeaten records go on the line in the males division of the Blue Diamond Previews at Caulfield.

Long Leaf and Run Naan are unbeaten from two starts while the Mathew Ellerton and Simon Zahra-trained Ollivander finished strongly on debut at Caulfield last month to make a winning start to his career.

They clash in Saturday's Listed 1000m race in what is expected to be a field of six in the absence of Fandral and Native Soldier.

Long Leaf's co-trainer David Hayes has indicated he would look to bypass the Blue Diamond Prelude with the colt and go straight into next month's Blue Diamond with four weeks between runs should the colt perform strongly.

"I've got a big opinion of Long Leaf. I think he's a quality horse," Hayes said.

"He'll be hard to beat.

"If he won and was strong on the line on Saturday, I wouldn't run him again until the Blue Diamond.

"I really think he's a (Golden) Slipper horse so I don't want to over-race him in the Melbourne autumn too much."

Long Leaf is at $3.40 and is shading Run Naan ($3.50) for favouritism, with Ollivander at $3.90.

The only debutant in the race is the Robbie Griffiths-trained colt Robe De Fete who is at $13.

Long Leaf won in Adelaide on debut in late October before taking out the Listed Merson Cooper Stakes at Sandown at his second start in November.

The Tony McEvoy-trained Run Naan won on debut at Bendigo in October before finishing strongly to take out the Group Three Maribyrnong Plate at Flemington in November.