Exciting colt Long Leaf is expected to go straight into the $1.5 million Blue Diamond after maintaining an unbeaten start to his career in the colts and geldings Preview at Caulfield.

Long Leaf won his two spring starts, including the Listed Merson Cooper Stakes in November, and returned from a let-up with a stylish victory in Saturday's Listed 1000m race.

After settling behind a line of three up front in the field of six, Long Leaf got the run through turning for home when debutant Robe De Fete hung out noticeably.

The $3.80 favourite, Long Leaf quickly chimed in passing the 200m to burst to the front under Damien Oliver and he had a half length to spare over runner-up Ollivander ($3.90).

The previously unbeaten Run Naan ($4.80) was another 1-3/4 lengths away third.

"I'd say he's our best chance for the Blue Diamond, for sure," Lindsay Park co-trainer Ben Hayes said.

"He was quite impressive today. I thought on the line he was full of running and we actually think he'll be better over 1200 metres.

"He's an unbeaten Fastnet Rock colt and he's a definite stallion prospect for the future now.

"I'd say more than likely he will go straight into the Blue Diamond."

Oliver said Long Leaf had a great attitude and was a real talent.

'He's got all the makings of a quality two-year-old," Oliver said.

Kerrin McEvoy, who won the Merson Cooper Stakes on Long Leaf, is expected to have first call on the ride in the Blue Diamond on February 24.

Sepoy in 2011 is the most recent colt to win the Preview and also claim the Blue Diamond.

Chris Symons lamented the interference Ollivander struck on the home turn but believes the colt will also be better suited at 1200m and is a Blue Diamond prospect.