Gai Waterhouse has her sights on a fifth Magic Millions Classic victory and believes Rosehill debut winner Certitude is the right horse to do it.

The filly was an easing favourite from $1.90 to $2.40 on Saturday with her main opposition Crazyonyou, a $3.30 chance.

Punters had it right with Certitude overhauling Crazyonyou to stretch out to a five-length win with Artistic Lass ($8) another 1-3/4 lengths third.

"She will be set for the Magic Millions and it will take a good horse to beat her," Waterhouse said.

"She will have one more run before then. I'm not sure if it will be at Wyong or in Queensland."

The $2 million Magic Millions (1200m) is at the Gold Coast on January 12 with the sales company's Wyong raceday on December 20.

Jockey Tommy Berry was glowing in his praise of the filly.

"She is as good as Driefontein," he said.

Driefontein gave Berry his first Magic Millions win earlier this year when she was awarded the race on protest from stablemate No Looking Back.

Like Driefontein, Certitude races in the purple and white colours of Denise Martin's Star Thoroughbreds syndication company.

She is by Not A Single Doubt out of Japanese-bred Debutante Rose and was a $140,000 yearling.

One of her owners, Francis Kennedy, was celebrating his birthday on Saturday and her win was compensation for stablemate Windjammer being beaten by Charlie Boy last week.

"We were the bridesmaid last week and Francis was disappointed," Waterhouse said.

"This is a great birthday present for him."

After a busy spring, Waterhouse is now taking a month off with New York and Aspen beckoning.