David Hayes is on a fact-finding mission with his leading Emirates Stakes contender Eagle Falls.

Success in Saturday's Group One feature at Flemington could open up a world of opportunities for the four-year-old or box him in as a specialist sprinter.

Eagle Falls failed at his only test at 1600 metres when sixth to Heart Of Dreams in the Australian Guineas last autumn but has since had throat surgery to correct his breathing.

Hayes said the operation had been an outstanding success so far but the Emirates was his longest race this campaign and would put him under increased pressure and ultimately decide his future.

"He made a noise in the Guineas in the autumn but he hasn't made a noise since and with maturity and improved breathing I am quietly confident he will be all right," Hayes said.

Eagle Falls, who has 54.5kg in the Emirates, has won six of his 11 starts including four of his six runs this campaign.

He came off two unplaced Group Two runs in the Gilgai Stakes and Caulfield Sprint to score a brilliant three-quarter length win over Turffontein in the Group Two Salinger Stakes (1200m) on Derby Day.

Hayes has likened Eagle Falls to his former star galloper Primacy who won the 1993 Emirates Stakes after finishing third in the Derby Day sprint.

"He reminds me of Primacy who carried a lot more weight (56kg) and won it (the Emirates)," Hayes said.

Hayes said the Emirates had been a long-range goal for Eagle Falls and that like Primacy he didn't race much at two and improved at three.

"He (Eagle Falls) is a very, very good horse and this race isn't just a throw at the stumps," Hayes said.

"I have planned it all year for him.

"He is a quality sprinter and if can run a mile (1600m) the options are endless but if he is a bit soft at a mile he is an ideal Newmarket (1200m) horse next autumn."

Eagle Falls has drawn the outside of the 15-horse field while Hayes will also start All American from gate six and Von Costa De Hero from barrier two.

Hayes said he was unsure what tactics to use on Eagle Falls but didn't rule out using the horse's natural speed to try and cross the field which also includes Cox Plate winner So You Think (barrier nine).

"All American is drawn to get a cushy run and if things go right he is capable of a surprise," Hayes said.

Hayes said it was hard to predict Von Costa De Hero but he was just as capable of an upset.

"I have purposely kept him five weeks between runs and he is an Australian Guineas runner-up at the course and distance," Hayes said.

"He needs cover, then luck and the breaks.

"If he gets them and he wins they will boo but I will be very happy to put up with the booing."