Golden Slipper favourite Sunlight has firmed for the $3.5 million race, after leading all the way to win the Magic Night Stakes at Rosehill.

But she may have a serious challenger in Written By who tightened from $7 to $5 after his Pago Pago Stakes win.

Sent out at $1.35 favourite for Saturday's final lead-up to the Slipper a week later, Sunlight never relinquished control of the race, beating Cristobal ($14) by 1-1/4 lengths with Sweet Ava ($13) another half length third.

Her trainer Tony McEvoy was pleased with Sunlight's effort.

"I thought she probably just levelled late," McEvoy said.

"That's OK.That's the gallop she needed and it will bring her on for next week.

"She got softened up a bit through the mid stages but the thing we've come to learn with this filly is she is tough.

"We just have to hold her together for the next seven days. It is very, very exciting for us."

Sunlight firmed from $4 to $3.50 for the Slipper with her jockey Luke Currie happy after she fought off the mid-race challenge from Setsuna who weakened out of calculations.

"She was really quick early and was even a little bit keen so hopefully that run takes the edge off her for next week," Currie said.

"Setsuna definitely made us work but she seems to thrive with more racing.

"She put on a bit of weight after the Magic Millions. She's a bit like her jockey in the fact she can put weight on pretty quick. This run will tighten her up for next week."