Julius will become Britain's first runner in the Ulster Harp Derby for three years when she runs at Down Royal on Thursday.
The £50,000 Listed handicap has been contested solely by Irish horses since Docklands Limo scored for Newmarket-based Brian McMath in 1997.
But Mark Johnston has chosen to run Julius, five times a winner from six starts this season, from his two original entries for the extended mile-and-a-half event.
"She is really flying at the moment," the trainer said.
"And the present fast ground will suit her. It will take a lot to beat her."
