Mujaazy and Pat Smullen (nearest) get the better of Bound and Emmet McNamara© Photo Healy Racing
The easy to back Mujaazy just got up to deny Bound in the opener at the Curragh, the Irish Stallion Farms EBF Fillies Maiden.
Second to Oh Grace on her debut at Leopardstown in June, the Dermot Weld trained daughter of New Approach then finished fifth to Capri at the Galway Festival.
Having opened at 11/4 on-course, the successful bay drifted out to 5/1 at the off.
Settled in second by Pat Smullen, she was ridden from two furlongs out, as she attempted to reel-in the front-running Bound.
The margin between them was diminishing throughout the final furlong, with Mujaazy edging to the front in the shadow of the post, prevailing by a head.
Bound, who was backed from 10's to 4's on-course, had to settle for second under Emmet McNamara for Aidan O'Brien. Bean Feasa was sent off the 2/1 favourite and she was a disappointing eighth under Kevin Manning for Jim Bolger.
O'Brien also saddled the third, and that was Key To My Heart (11/4). This son of Galileo ran on well in the final furlong, and finished a further half a length back under Donnacha O'Brien.
Dermot Weld said afterwards: "She stays well, is tough and genuine.
"She'll probably just run once again, most likely in the Silken Glider, to get a bit of black-type before the year is out.
"She wants every yard of a mile and will make a lovely mile-and-a-quarter or mile-and-a-half stakes filly next year.
"The little bit of ease did help."
Additional reporting by Gary Carson