Adelaide three-year-old Eclair Big Bang has confirmed his Caulfield Guineas aspirations with victory in the Prelude on Sunday, running down New Zealand visitor El Roca.

Dominic Tourneur timed his run to perfection on the Phillip Stokes-trained Eclair Big Bang ($13) to beat El Roca ($14) by three-quarters of a length in the 1400m Group Three race.

Favourite Long John ($3) hasn't lost any admirers, charging home to finish another short head away third, maintaining his position at the head of betting for the $1 million Group One Caulfield Guineas (1600m).

Stokes has always had a high opinion of Eclair Big Bang and says it is all systems go for the Guineas but he wants to see him settle even more to be at his best in a couple of weeks over the 1600 metres of the Group One race.

"We've brought him along slowly this preparation and brought his fitness up slowly. He's getting to peak fitness now," Stokes said.

"He still has to learn to relax a bit more to run the mile out I think, but we'll put a bit more work into that and he'll be there on Guineas day."

Eclair Big Bang won his first two starts in Adelaide before running third on his Melbourne debut in the Group Two Danehill Stakes (1200m) down the Flemington straight.

Tourneur took plenty of heart out of that performance and knew the horse would be better suited getting cover in the Prelude and racing around a bend.

"He put them away nicely today," Tourneur said.

El Roca bounced out and took up the running with Group One winner Romantic Touch settling on his outside.

The Kiwi kicked away rounding the home turn but couldn't hold off Eclair Big Bang in the final 100m.

Jockey Craig Newitt believes El Roca will be better again in the Guineas.

"His run was super and he'll be hard to beat (in the Guineas)," he said.

Trainer Peter Snowden is also looking forward to the Guineas with Long John, who settled eighth in the run and was forced to come wide around the turn before making good ground late.

"He was excellent," Snowden said.

"He got a bit too far back and was shunted wide on the corner but he got home really well."