Australia won his second Derby in three weeks as he followed up his Epsom success with a brilliant display at the Curragh.

Living up to his billing as a true champion, the bred-in-the-purple colt gave trainer Aidan O'Brien an amazing 11th triumph in the Dubai Duty Free Irish Derby as he trotted up to justify his restrictive odds of 1-8.

Winner of the Investec Derby, Australia followed in the hoofprints of his sire, Galileo, who took this prize in 2001, and his dam, Ouija Board, the Irish Oaks winner in 2004.

The race went to plan and turned into a benefit for the Ballydoyle and Coolmore teams. Joseph O'Brien, riding his second Irish Derby winner, sat in third place as stablemates Kingfisher and Orchestra set a good gallop.

He made his move on Australia early in the straight before leading a furlong out and going on to win as he liked.

Eased home, he was two-and-a-half lengths clear of Kingfisher (25-1) in second and Orchestra (12-1) in third as the O'Brien team filled the first three places.

Australia was sent off at a prohibitive price after the race was reduced to five runners with the late defections of Epsom runner-up Kingston Hill and the winner's stablemate Geoffrey Chaucer.

However, the expectant crowd got the result they had hoped for as Australia completed the Derby double with consummate ease.

O'Brien snr would like to see Australia drop in trip, with races such as the Irish Champion Stakes at Leopardstown in September and the Juddmonte International at York a month earlier under consideration.

The trainer said: "He has so much class that he'd be very comfortable back at a mile. For him to get a mile-and-a-half the way he does, it's incredible. He just relaxes in his races. Pace is his big thing, he just travels.

"I'd definitely think about the Arc, but you wouldn't want to run him on bad ground. He might get a little rest now, the lads will decide that themselves."

Joseph O'Brien believes Australia could have even more to offer over a shorter trip. He said: "This is a special horse. He has a massive engine and we still haven't seen the best of him. I'd love to ride him at a mile-and-a-quarter, I think that's going to be his thing on fast ground.

"His attitude and pace set him apart from the others. He's a great mover and he's so well balanced. When I walked him down to the barn and came back before the race for the parade, he'd have stayed asleep.

"The Irish Derby is one of the races you watch growing up. To be riding in the race is a dream and to win it is unbelievable."

Teo Ah Khing, fellow part-owner of Australia with John Magnier, said: "This is one of the most special horses we ever could find in the world.

"The environment here is so unique and special and I think there are many people in China that would love to come if they knew of this special quality here."