"It is quite a unique course but she seemed to handle it very well.
"We got some good, positive feedback from her jockey, Michael Hills, about how she galloped, too."
Australian jockey Craig Williams rode Ortensia when she finished ninth in the group one King's Stand Stakesat Royal Ascot this month but themare will have a new jockey at Newmarket.
Messara revealed that champion English jockey William Buick had been booked to ride Ortensia.
Buick, 23, who is challenging Ryan Moore for the English jockeys title this year, has won four group one races this month alone, including last Sunday's Eclipse Stakes on Nathaniel.
"It's good to have a rider with local knowledge," Messara said.
Ortensia, winner of the group one Al Quoz Sprint in Dubai this year, started favourite at Royal Ascot but has become something of a forgotten horse for the July Cup with English bookies offering as much as 16/1 about the Aussie mare.
"There were a few excuses for what happened at Royal Ascot," Messara said.
"I think you will see a different horse in the July Cup - she is going as well as ever."
Ortensia isn't likely to be the only Australian sprinting presence at Newmarket.
Godolphin is expected to run 2011 Golden Slipper winner Sepoy and talented Soul in the July Cup.
Sepoy hasn't started since failing at the Dubai World Cup meeting.
A five-time group one winner under trainer Peter Snowden, Sepoy is likely to have his final race start in the July Cup before returning to Australia to stand at Darley Stud in the Hunter Valley next spring.
Soul, also previously trained by Snowden, ran a blinder to finish fourth behind Black Caviar in the Golden Jubilee Stakes at Royal Ascot.