The 5-1 favourite found himself travelling last of 30 runners in the valuable two-mile handicap, the prize fund for which has been boosted to €600,000 this season.
Jockey Wayne Lordan remained patient on the inner rail, weaving through almost every one of his rivals stalk the leader, Willie Mullins’ 6-1 shot Echoes In Rain.
Under a masterful ride, the Ballydoyle colt lunged at the line to prevail by a mere neck, capitalising on a bottom-weight of just 8st 9lb.
“He’s a horse with an awful lot of ability. We thought in the winter that he was our Derby horse but when we started to race him, he became very shy and mentally very backward,” O’Brien said.
"Incredible" - Aidan O'Brien hails Wayne Lordan after a Curragh masterclass
“We decided to take our time with him and not throw him in a Leger or anything like that and give him time to mature.
“Today we were drawn out so far (18) that we thought we couldn’t win with a three-year-old that was so shy. Obviously Wayne gave him the most incredible ride.
“Ryan (Moore) rode him the last day and felt the trip was going to suit him, but it’s like a cavalry charge out there they go that hard and that fast. It’s like the Grand National on the Flat.
“Wayne kept nursing him and he’s obviously a horse with a huge amount of ability.
“Next year he’s going to be something different. He’s been a baby and didn’t race last year. He’s massive with a beautiful pedigree and looking at him today, he’s going to be very at home at Cup trips.
“All credit to (former Horse Racing Ireland chairman) Joe Keeling for putting on this race and making it happen. Everyone has a chance at a big pot and the Curragh had the place in super shape for 30 runners.”
Lordan was impressed with Waterville’s performance and said: “Aidan said he was very well and to take your time in the race and he’ll come on the bridle at halfway. He told me to ride him with loads of confidence.
“He knew the horse better than me but literally at halfway he did come on the bridle.
“I switched him out and he hit the line well. He didn’t kill himself but he was running at the line which was a plus.
“He has a big engine and going that trip, when you have a horse underneath you, then you can go where you want.
“I enjoyed it – well, when I got to the line in front I enjoyed it!”Racing TV is THE place to watch all the best racing live from both Britain and Ireland and you can try it for yourself for FREE with a 31 day trial!
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