Lurgan-based Isabels Boy was edged out of the €120,000 Irish Derby in the first semi-final at Shelbourne Park, won by Tyrur Sugar Ray.
Gary Silcock's black dog had every chance to qualify despite not leading as had been expected.
Outsider Carrowgarriff made the best start ahead of Isabels and they went round the first bend in that order chased by Slippery Robert on the outside.
The trio closed up on the penultimate turn while the strong stayer Tyrur Sugar Ray cut back the leeway and hit the front.
The powerful stayer wasn't going to be caught and reached his second Derby final, beating Slippery Robert by three lengths in 29.87 with Carrowgarriff qualifying in third.
Tipperary's Graham Holland, in sparkling form with five winners on the night, saw his Cabra Buck make all in the second semi, holding off Ballymac Vic by two lengths in 29.83.
Kereight King just got the better of Borna Gem for third but will not take his place in the decider after breaking a toe.
The final line-up in trap order is: Ballymac Vic; Tyrur Sugar Ray, Carrowgarriff, Kereight King, Cabra Buck, Slippery Robert.
Meanwhile at Drumbo Park, Allen Agnew's brilliant Belfast runner Kincraig Rory clocked the fastest run of his career (17.80) in a sprint.
Showing good pace from trap one, he handled the challenge from Bridgetown Noel and had an easy two and a half lengths in hand from Quarterland Mary who finished well to deprive Noel of second spot.
Over four bends, Blenhiem Tricks – from Ronnie McKeown's Hillsborough kennels – was an emphatic five-lengths winner in a superb 28.64 (525), leading all the way and putting five lengths between himself and Tang Mark One.