Taking up the running heading into the dip, the 3-1 winner never looked like being caught, scoring by a length and a half and a head as he provided the winning rider's father, Aidan, with a ninth triumph in the colts' showpiece.

Roger Teal's 50-1 chance Tip Two Win ran a stormer to finish second, with the Charlie Appleby-trained 5-2 favourite Masar in third.

Elarqam ran well just out of the places in fourth, while Roaring Lion improved in leaps and bounds for his Craven run in fifth.

Donnacha O'Brien told ITV Racing: "A huge thanks to all the owners for giving me the chance to ride him and especially to dad for the faith in putting me on him in the first place.

"It's very special. Obviously, I'm winning this race and riding in big races because of the position I'm in. I'm just very grateful.

"He's a very good horse, he's a proper horse."

With O'Brien senior in America supervising Mendelssohn in the Kentucky Derby, Paul Smith, son of co-owner Derrick, said: "It was really eyecatching, Donnacha couldn't speak too highly of him. He said when he quickened it was all over in a flash.

"He probably got there sooner than he wanted to, but he had so much horse under him. It's very exciting when they have that speed and look like they'll get further. All things point to June (Derby) now."

He added: "That's 300 Group Ones wins for Aidan and Donnacha's first Classic. They are an incredible family."

O'Brien's eldest son, Joseph, said: "It's very special. I thought Donnacha gave him a lovely ride.

"He's definitely a good horse. He's travelled and went through the line well."

Teal was proud of the effort of Tip Two Win.

He said: "I can't put it into words. I'm pinching myself.

"I was trying to watch it out the front, but I didn't bring my binoculars so all I could see was his white breast girth.

"When he came out of the dip I thought 'oh my God' - I'd got a chance of winning the Guineas and then he flashed by me. I was about 50 yards from the line.

"It's amazing. We knew we had a decent animal. He was only a 50-1 shot because he was trained by me.

"It's just a proud moment for us and I'm delighted for Anne (Cowley, owner).

"We entered him for the St James's Palace Stakes (at Royal Ascot), so I guess it will be that or the Jersey.

"We'll just get over today and digest it and see what happens."

Appleby said of Masar: "He lost nothing in defeat there. He has progressed with every run. William (Buick) was very happy that he got into a nice rhythm there. He said he just felt when they quickened up he just lacked that turn of foot.

"He is a horse with a Derby pedigree and that's where we will head now, all being well."