The strength of Gai Waterhouse's hand in Saturday's Hawkesbury Gold Cup could hinge on the decisions of a rival trainer.

Waterhouse has Ecuador and Pheidon safely in the field of 16 while stablemate Frespanol has been made an emergency and needs three scratchings to gain a start.

But his chances of earning a first shot at stakes company will be boosted significantly if the forecast rain arrives.

Hawkesbury was rated soft on Thursday and could deteriorate further with rain expected on Friday and Saturday.

Premier trainer Chris Waller has seven runners in the Hawkesbury Gold Cup field and confirmed at least two of them won't start if the track is a genuine heavy.

Waller doesn't want to risk flattening German import Flamingo Star on a wet track at his Australian debut and feels Strawberry Boy doesn't perform to his best in heavy conditions.

"We've had a lot of rain over the past few weeks and the tracks are similar to the middle of winter, they're waterlogged," Waller said.

"A lot of our horses are first-up, or a bit soft, or not suited to the wet so it would be no surprise to see a few of them scratched come Saturday morning."

Waterhouse last won the Hawkesbury Gold Cup with Beauty Watch in 2006 and while she expects the resuming Pheidon to need the run, she is quietly confident about the chances of Ecuador.

The five-year-old made an encouraging return to racing when he was narrowly beaten by Saturday's rival Rugged Cross at Randwick earlier this month.

It was his first run in more than a year and while horses can be vulnerable second-up off a lengthy break, Waterhouse says Ecuador is showing all the right signs around the stable.

"I suppose they can (be vulnerable) but he's very happy and you couldn't tell by watching him," Waterhouse said.

"He's done very well, he's a very nice gelding.

Frespanol has three placings on soft tracks and Waterhouse is keen for him to back up from his fourth to Dowdstown Charlie at Randwick on Saturday.

Tulloch Lodge will also be represented in the Group Three Hawkesbury Guineas by the promising Najoom.