River Racer is unlikely to be regarded among Queensland's greatest mares but she will be remembered as one of the most honest to race in the state.

River Racer needs only to finish in the placings in the Listed Sunshine Coast Cup (1400m) on Saturday to take her earnings past $800,000.

It is a marvellous return for the owners of the mare who cost just $15,000 at the 2015 Magic Millions March Yearling Sale.

Trainer Les Ross said there was a lot more to the River Racer story than just a mammoth return on an investment.

"What people don't realise is that she has had a lot problems with her legs like knee chips among other things" Ross said.

"It is why she is considered best on wet tracks and she has had to overcome a lot. But four of her wins have been on good surfaces which is a credit to her big heart.

"I could have won a dozen races with her by now if I had wanted to keep her in weaker company.

"But she has just about always raced in top company. She ran third in the Listed Calaway Gal Stakes at her second start and she has pretty much always raced in Saturday company."

Since she won a Class Six at Doomben in May, River Racer has had nine starts in feature races.

At her most recent she was second to Outback Barbie in the $1 million Magic Millions QTIS Plate last Saturday week at the Gold Coast.

"The QTIS race was her target this campaign but the Sunshine Coast race was also on her radar," Ross said.

"Her two runs at the Sunshine Coast over 1400 metres were both in the (Listed) Glasshouse Handicap. She was third in 2018 and won it last year.

"So it is obvious she is well and truly up to Saturday's race with a half kilo over the limit."

The Sunshine Coast was drenched with 150mm of rain in the past week and the likelihood of a soft track will also suit River Racer.

Ross said after Saturday's run River Racer would go for a spell with no firm plans in place.

"There is nothing for her up here after Saturday so she can have a break," Ross said.

"But who knows we might even have another crack at the Millions QTIS in a year's time. After all the money is very good."

Brad Stewart takes over from Sydney rider Nash Rawiller who was aboard in the Millions race.

"Brad is a patient rider and he suits River Racer's style. He should be able to get a nice run from barrier four," Ross said.