Varboss has yet to win a race but could emerge as a Derby prospect at Sandown.

The Jason Warren-trained gelding has shown enough talent for connections to be looking at the South Australian Derby in May.

Those ambitions will be put to the test in an 1800m race for three-year-olds on Wednesday.

"If he runs first or second tomorrow I'd say we're still very much right on track," Warren said.

A son of Street Boss, Varboss is out of Varevees who was a Group-winning stayer in France and competed in the 2008 Melbourne Cup for her owner Rick Jamieson, widely known as the man who bred Black Caviar.

Varboss has been placed in his three starts this campaign including a narrow second to Honey Steel's Gold in a Sandown midweek race over the same distance last time out.

That has Warren confident Varboss is close to a breakthrough win.

"I really like him," Warren said.

"He's probably unlucky not to have won a maiden yet but he's been very consistent this preparation.

"He'll be hard enough to beat tomorrow."

The Peter Snowden-trained Argos, a last-start 3-1/2 length winner at Werribee, is the early favourite and the one Warren rates the hardest to beat.

Argos finished ahead of Varboss in a Moonee Valley race over a shorter journey two starts ago and Warren said he expected Varboss would have to give him a start on Wednesday from his wide draw.

While Varboss chases a maiden victory, stablemate Danger Close gets the chance at back-to-back wins in the Vale Roy Higgins Handicap (1000m).

Danger Close scored over the same course and distance earlier this month but Warren conceded a rise of 2kg and a bigger field was against him.

"In saying that he's in terrific order and Craig Newitt has got the key to how to ride him, and he'll run very well tomorrow," Warren said.

Newitt has ridden Danger Close five times including to two of his three wins.

Meanwhile, Warren was encouraged by stable star Bel Sprinter's fourth in Saturday's Challenge Stakes at Randwick ahead of his attempt at back-to-back wins in the Group One Galaxy.

Kerrin McEvoy rode the gelding in the 2013 Galaxy but Newitt will be his partner this time around.