Whitecliffsofdover won the Free Handicap over seven furlongs of this mile in April, while Sir John Lavery finished one place ahead of his stablemate when fourth to Suedois in the Boomerang Stakes at Leopardstown on Irish Champions Weekend.
O'Brien won the Group Two last season with Cougar Mountain.
Suedois' trainer David O'Meara saddles the eight-year-old Custom Cut, who lifted this race in 2014 but was only seventh in the Boomerang on his latest start.
Another eight-year-old in the nine-strong line-up is Ruth Carr's evergreen Sovereign Debt, while an international feel is provided by South African challenger Whisky Baron, trained by Brett Crawford.
The field is completed by Jallota, Mustashry, Zonderland and Beat The Bank.