A heavy track and race fitness paved the way for My Sabeel to score an unlikely Group Three victory at Randwick on Saturday.

Trainer Kevin Moses admitted the mare was racing out of her grade in the Toy Show Quality (1300m) and only nominated her when he saw the weather forecast for rain.

My Sabeel ($9.50) vindicated Moses's decision, again showing her liking for the wet to thump her rivals by 4-1/2 lengths with Bennetta ($6) doing best of the chasers.

The victory took My Sabeel's record on heavy tracks to two wins and four placings from eight attempts.

"It's well above her grade but she gets through the ground," Moses said.

"A lot of the other fillies and mares weren't fit and she's hard fit."

Moses is the seven-year-old's fourth trainer and the mare has been rejuvenated under his guidance.

He credits his wife Jenny with managing My Sabeel's tricky temperament to lay the platform for her career-best form.

"She was cranky when she came to us but Jenny takes her for a walk every day, gives her a pick of grass and it's changed her whole attitude," Moses said.

"She's a happy horse at the moment."

Moses also revealed My Sabeel's owner Frank Scali almost sold her recently for a fraction of the $75,000 first prize money she claimed on Saturday.

"Frank got offered $5000 for her and Jenny said `let's take it' and since then she's won probably $150,000," Moses said.

Favourite Gypsy Diamond settled near last and worked home late for fifth while Tommy Berry was satisfied with the performance of Group One winner Diamond Drille who finished eighth under her big weight.