Jason Coyle concedes training two-year-olds is not yet his forte, so it will be up to River Bird to indicate whether she is worthy of a start in the $3.5 million Golden Slipper.

The filly is second-up into the Group Three Widden Stakes (1100m) at Rosehill on Saturday, and Coyle is confident she can improve on a luckless debut at Randwick last month.

However, whether she is capable of earning a start in the world's richest race for two-year-olds juveniles at Rosehill on March 24 is uncertain.

"I'm not a master two-year-old trainer. I let them tell me if they're ready to go to the races," Coyle said.

"I don't know if she's a furnished Slipper horse. We'll see how she measures up and be guided by her more than anything."

River Bird over-raced early over 1000m in her first start and was then blocked on the turn home before placing fourth.

"Once she got clear she was very raw and laid out under a bit of pressure," Coyle said.

"She's got a lot of improvement in her and I think she's a genuine hope from a soft draw."

Although Coyle played down his two-year-old record, the trainer won the 2009 Champagne Stakes with Onemorenomore and T J Smith Classic with Linky Dink in his previous role with Patinack Farm.

But he said there was no pressure for River Bird and her as yet unraced stablemates to perform ahead of their time.

"Memes is probably the best advertisement for letting horses do what they need to do," he said.

The four-year-old broke her maiden in April last year and has won another five races.

"Time and patience has proven a good formula for her," Coyle said.

Memes also runs at Rosehill where she will compete in the Group Two Expressway Stakes (1200m).

"Weight-for-age against well-performed horses like million dollar earner Global Glamour is a massive step for her," Coyle said.

Global Glamour led the market at $2.90 on Friday for co-trainers Gai Waterhouse and Adrian Bott.