Rocket Man claimed the concluding maiden to give both Aidan O'Brien and Johnny Murtagh doubles at the Curragh.
The son of Montjeu finished with a flourish in the final furlong to get up for a half-length success over Captainofthefleet
"We thought he was a nice horse last year," said O'Brien of the winner.
"Joseph's horse (9/4f Bold Quest had a run and we are worried about them all having runs. He's a nice moving horse."
Murtagh had earlier struck on Kargali for trainer Luke Comer while O'Brien had claimed the first with newcomer Samuel Morse partnered by Seamus Heffernan.
