Kerrin McEvoy expects the rain in Sydney will help offset the outside barrier of Fiesta in the Golden Slipper.

"The rain is what gives us hope," McEvoy said.

McEvoy feels the elements can bridge the gap between the market leaders Sunlight and Written By and the rest of the field in the $3.5 million Group One feature at Rosehill on Saturday.

"Written By's got through it (soft ground) but it's an unknown for Sunlight," he said.

McEvoy had no concerns about Fiesta handling a wet track, given her only win, the Group Three Widden Stakes at Randwick on March 3, was on soft ground.

"Fiesta has won and placed on soft. She worked on Monday on some juicy ground and was really good in her work," he said.

Fiesta was a $19 chance on the TAB market on Wednesday but McEvoy, who won the 2011 edition on Sepoy, was still optimistic she could give trainer Chris Waller with his first Golden Slipper.

"Obviously we're right outside but a lot of things can happen. We're not really an on-the-speed filly anyway. We're a midfield-type runner looking for a bit of cover," he said.

McEvoy said her last-start second to Golden Slipper rival Seabrook in the Group Two Sweet Embrace Stakes was an encouraging sign.

"It was a good effort, We were wide that day with no cover and just got run down by Seabrook, who's no slouch," he said.

"She lost no admirers to my mind with that defeat and has come on nicely since."