Jason Coyle is convinced White Moss can go close to matching the stakes deeds of older sibling White Sage as he tests the waters at Randwick on Saturday.

The free-wheeling grey mare - raced by the Esplin family, the same ownership group as for John O'Shea's former striking listed winner White Sage - will face her toughest test in the group 3 Nivison.

It is not only the pair's appearance that is strikingly similar, but their records are starting to also resemble one another.

White Moss has won four of her first seven races, while White Sage retired a five-race winner from just seven career starts.

"She's always been a really sharp trackworker and she's always showed ability on the training tracks," Coyle said of White Moss. "The owners raced White Sage with John O'Shea and they said White Sage was much the same; being a very, very good trackworker.

"Until you take them to the races they haven't proved themselves, but White Sage proved herself a very good mare. This mare, although she hasn't done it, albeit everything being well and she's sound she should graduate to at least stakes level I would hope."

White Moss will headline Coyle's assault on the Nivison, which also includes the resuming Albury Guineas winner Siren's Fury.

But it is his Mossman mare who will attract most attention with Jason Collett taking over the ride from Kathy O'Hara, who will ride Single Gaze in the $3 million Caulfield Cup in Melbourne on Saturday.

"It's sometimes difficult for mares from one preparation if they're in form to return and race well and she did that first-up at Canterbury," Coyle said. "She might be one just a bit better than working her way through the grades.

"She deserves her chance in a black-type race. She probably runs into a couple of class mares in Ronny's horses [Daysee Doom and Dixie Blossoms], but they've got to deal with dropping back from a mile.

"She's done nothing wrong in her last five starts and there is that possibility she could have come into this winning her last five."

White Moss' stiffest opposition might come from Ron Quinton's pair Dixie Blossoms and Daysee Doom, both of who will drop back to the sprint trip after running the quinella in the Angst Stakes over a mile a fortnight ago.

Coyle's confidence with White Moss is tempered with caution about Siren's Fury, who has had two quiet trials after placing in listed company in Sydney and Brisbane last campaign.

"She's a nice mare and she's done nothing wrong," Coyle said. "She got herself stakes-placed a couple of times last preparation.

"Her trials have been good coming back this preparation. The 1200 [metres] is going to be a tad sharp for her, but if she can acquit herself well she's in for a really nice preparation whether that's staying in Sydney for benchmark races or there is a possibility of maybe shooting down for a listed mares race later in the [Melbourne] carnival."

The ultimate racing form guide with free tips, live odds and alerts for all racing.