By Mathew Toogood

SYDNEY, Aug 28 AAP - The Cox Plate dream is alive for connections of glamour mare More Joyous who defied a wide barrier and big weight to score a brilliant first-up win at Rosehill.

A bigger, stronger More Joyous was eased back in the field by Nash Rawiller and the Group One winner came with a barnstorming finish to claim Saturday's Listed Sheraco Stakes (1100m).

Delighted owner John Singleton declared the Cox Plate (2040m) at Moonee Valley was the main mission for the four-year-old this spring.

"That was unbelievable," Singleton said.

"This is the preparation for her. She hasn't lost any weight, I think she put on 100 kilos in her spell, and by giving her such an easy run as a three-year-old I think she'll go on with it.

"The Cox Plate is the objective and if I'm proven wrong she can come back and be a Lightning (Stakes) horse."

More Joyous, returning to the races for the first time since early March, lumped 59kg and jumped from barrier 10 in the field of 11.

Rawiller was content to have More Joyous ($2 fav) sitting eighth, one off the fence, and the mare produced an outstanding turn of foot in the straight to defeat Girl Hussler ($13) by a length with Sister Madly ($6) three-quarters of a length away third.

While the Cox Plate in late October is in the sights of More Joyous' connections, a Group One target in Sydney awaits before the mare heads to Melbourne.

Trainer Gai Waterhouse believes the Epsom Handicap (1600m) at Randwick is at More Joyous' mercy.

"She's an outstanding mare, you've just seen the Epsom winner in my opinion," Waterhouse said.

"She's got blistering speed, she's got the most sensational turn of foot and she's just on the improve.

"Whatever she's done today there's so much improvement I can't tell you."

The Sheraco Stakes 12 months ago was the last time More Joyous tasted defeat.

A first-up third in that race was followed by wins in the Tea Rose Stakes and Flight Stakes, then she returned in the autumn to win the Light Fingers Stakes and Surround Stakes.

Rawiller said Saturday's win was probably the best More Joyous had ever gone first-up.

"She was awesome today and did it very easy," Rawiller said.

"I think she's the best we've had her. She's a lot stronger than last preparation and I really think she's there to go on with it now."