Trainer Aidan O'Brien accounted for three of the first four finishers, including the disregarded winner who was ridden to victory by Colm O'Donoghue. Astronomer Royal went off at 4-1 as the lesser part of a three-horse entry that included the O'Brien runners Honoured Guest, who finished third, and the fast-closing Excellent Art, who checked in fourth after being held up in traffic a furlong from the wire.
Astronomer Royal, last in the field of 14 at the four-furlong point of the one-mile journey, had two horses beaten at the head of the straight. After angling to the outside, the Classic Star-bred son of Danzig made good headway through the last quarter mile, reaching the lead in the final 100 yards and defeating the Jim Bolger-trained Creachadoir by a half-length.
Derrick Smith owns the winner as well as the inexperienced Honoured Guest, who ran on well to finish two lengths behind the bay colt Astronomer Royal, out of the Easy Goer mare Sheepscot.
The 7-2 favorite Battle Paint was headed by Creachadoir more than a furlong from home and faded quickly to finish ninth.
O'Brien, who claimed his third Poulains win, told Racing Post, “All our horses come on after running in trials and Astonomer Royal was ready to go on this occasion. Colm has been riding with great success in India and I was delighted he was on board the winner.
“Our string has been coming along nicely all year and we have great depth. So many have group I class. The horses who ran today could all be involved in races at Royal Ascot.”
O'Donoghue, who enjoyed his first group I success in France, added, “Astronomer Royal was where he was when I wanted, and he showed lots of speed in the straight. He is certainly a very good horse.”
The final time was 1:37.1 on good going.