The legendary Istabraq carried the owner's green and gold silks to a joint-record three victories in the Champion Hurdle at Cheltenham and is widely regarded as one of the greatest two-milers of all time.
Jezki, trained by Jessica Harrington, won the Champion Hurdle in 2014, one of eight top-level triumphs.
The nine-year-old returned from a near two-year absence with victory at Navan in January, but suffered defeat on his next start at Gowran and disappointed in both the Stayers' Hurdle at Cheltenham and on his most recent appearance at Fairyhouse in April.
Harrington, who also saddles talented mare Forge Meadow, said: "Jezki seems to be in great form. We thought we'd start him off early and see how the winter pans out."
McManus' retained rider Barry Geraghty has sided with Gavin Cromwell's stable star Jer's Girl in this weekend's Grade Three contest.
The dual Grade One-winning mare made a successful reappearance on the Flat at Roscommon on Monday and makes a swift return to action.
Mark Walsh partners Jezki.
Last year's winner Ivan Grozny defends his crown for Willie Mullins. The champion trainer is also represented by Coquin Mans, who is four from four since arriving from France.
The six-strong field is completed by Ellmarie Holden's Ex Patriot.
Grade Three honours are also up for grabs in the Joe Mac Novice Hurdle.
Mullins fires a twin assault with Sayar and Law Girl, while Henry de Bromhead sends Classic Theatre and Special Diamond into battle.
The Gordon Elliott-trained Morgan and Housesofparliament from Joseph O'Brien's yard are the other contenders.
Rathvinden (Mullins), Potters Point (Elliott) and The West's Awake (Edward O'Grady) feature among seven runners in the Grade Three Like A Butterfly Novice Chase.
Eleven go to post for the feature Flat race on a mixed card, the Group Three Coolmore Stud Home Of Champions Concorde Stakes.
Onenightidreamed, trained by Fozzy Stack, makes his first appearance since winning a conditions race at Tipperary in April.
Gordon Lord Byron (Tom Hogan), Silverkode (Joe Murphy) and Psychedelic Funk (Ger Lyons) have also been declared.