Ryan Moore’s overnight trek from Australia to ride the Derby favourite John F Kennedy at Leopardstown tomorrow signals the start of a new era and the end of another.

Joseph O’Brien’s tenure as No.1 jockey at Ballydoyle lasted little more than three years, yielded multiple classic victories, including two Epsom Derby wins, a pair of jockey’s championships, and was a miracle of willpower considering Aidan O’Brien’s 21-year-old son stands at six feet tall.

Moore’s appearance at the first significant Derby trial of the year, albeit having undergone a punishing trip from the other side of the world, only confirms O’Brien Snr’s comments about the Englishman riding his “main horses” this year. Such an arrangement tallies with Ballydoyle’s history of employing the best to ride the best.

Moore’s presence at Sydney’s Randwick track in the early hours of this morning testifies to his global profile.

A trio of Group One rides climaxes with the ex-O’Brien trained Cox Plate winner Adelaide in the Queen Elizabeth Stakes at 7.35 this morning, after which Moore will be heading to Mascot airport post-haste to team up with the Derby favourite among four booked rides for O’Brien.

John F Kennedy is a general 4-1 favourite for Epsom glory in June and it will be a major shock if that position isn’t maintained after facing just two opponents in a Group Three feature that famously produced Aidan O’Brien’s first two ‘blue-riband’ winners, Galileo and High Chaparral.

Moore will also team up with Qualify in the Group Three 1,000 Guineas Trial. The Ballydoyle hope’s opposition will include a cross-channel raider in Calypso Beat, Jamie Spencer’s sole ride on the card.

Other top jockeys Andrea Atzeni and James Doyle will be flying into Leopardstown. Doyle has two rides for Godolphin, including Portage Boy in a 2,000 Guineas Trial. Kevin Manning maintains the partnership with the Eyrefield Stakes winner Parish Boy, a highly rated Jim Bolger trained colt that should have little difficulty with soft ground conditions.

Dermot Weld’s Zawraq impressed in his maiden win here last October and looks another prime Trial contender but the in-form trainer also looks to have good chances with Zannda in the opening maiden and Sierra Sun in a nine furlong handicap. Weld’s Cheltenham festival winner Windsor Park has a tough follow-up test in Gowran’s finale today against the 102-rated Shu Lewis but it’s a test he can pass.