O'Brien's Battle for Kentucky
The Ballydoyle supremo is keen to land America's premier race and this season's candidate travels across the Atlantic with high hopes.
An American-bred son of War Front, the three-year-old showed his class and ability to handle an artificial surface when winning the UAE Derby at Meydan in March.
Ryan Moore has made the trip Stateside for the ride, although the jockey will immediately jet back to Newmarket for the second day of the Guineas meeting.
"He's in good form, obviously nobody knows about (how he'll handle) the dirt until he runs on it," O'Brien said. "We were very happy with him in Dubai. He's usually a fast breaker, he travels well and we're looking forward to the race."
Heading the betting for the 10 furlong contest is Shug McGaughey's Florida Derby hero Orb, the mount of Joel Rosario.