Power employed an electric turn of foot to land the Abu Dhabi Irish 2,000 Guineas at the Curragh.
Trained by Aidan O’Brien and ridden by his son, Joseph, Power, who disappointed in the Newmarket Guineas on his seasonal bow, was sent off an uneasy 5-1 chance.
Having seen his stablemate Daddy Long Legs open up a big early advantage, Power flew in the final furlong to pip Bryan Smart’s outsider Foxtrot Romeo, with Reply, another O’Brien runner, in third.
Daddy Long Legs, who was pulled up in the Kentucky Derby, set the early pace under Colm O'Donoghue, with fellow O'Brien inmate Wrote the only one to follow his lead.
The pair built up a healthy advantage over the rest of the field and were still well in control two furlongs out.
However, the distress signals were out thereafter with O’Donoghue pushing his mount along while Seamie Heffernan aboard Wrote was also getting to work.
With just a furlong left to run, the field still had plenty of ground to make up, but first Foxtrot Romeo and then Power emerged to challenge.
Power’s change of gear was thoroughly impressive and when O’Brien jnr finally got his head in front, the Oasis Dream colt pulled a length clear in style.
Foxtrot Romeo, a 33-1 chance, outran his odds to claim the runner-up prize with Reply filling the frame at 25-1.
Richard Hannon’s Trumpet Major was sent off the 9-4 favourite but never looked dangerous, while Sea The Stars half-brother Born To Sea ran on to make good late headway behind the principals.
Power is owned by the Coolmore team and John Magnier said: ``The ground makes a big difference to him. He didn't have to have fast ground last year, but he'd been working well since we got good ground and he just got stuck in the mud at Newmarket.
“It looked like Daddy Long Legs would win but I think Power has to be ridden to come late, I think that’s something they have learnt about him.”
The winning rider said: ``They went a very good gallop and my horse was nice and relaxed. I was creeping away down the rail and I had plenty of cover. I didn't want to get to the front too soon and the lads were a long way in front.
“I wasn’t sure if I was going to get to them but in fairness, he quickened up very well when I needed him.
“Daddy Long Legs is a confirmed front runner, he loves making the running and he stays very well. He was always handy in Dubai and he made the running when he won in Newmarket last year.
“He went a nice pace and Wrote is an uncomplicated horse and I just wanted to take my time on my fella and when I knew there was going to be a nice gallop on, I didn’t mind doing that.
“He stuck to it to the line. It is a big advantage to have a look through the form and see where the pace is coming from.
“I have to thank Ryan Moore, he rode the horse at Newmarket and in fairness, he said he felt like a good horse for the first part of the race and he just didn’t come down the hill on the ground.
“He said that he thought this fella was the one so a big thanks to him. He’s a classy horse and he has plenty of speed.”
The victorious handler was thrilled to add to his wins in the English 1000 and 2000 Guineas earlier this month.
“I’m delighted, what can I say. I’m privileged and delighted,” said O’Brien senior.
“We were very happy with Power last year. At Newmarket it was his first run of the year on very soft ground and Ryan rang during the week and just said ’he felt like a serious horse during the first half of the race but then he lost in the second half of the race’ and we put that down to maybe needing the run and the soft ground.
“Ryan was anxious that Joseph would ride him (from the other Ballydoyle runners) and how right he was. I’m delighted it worked out so well.”