The Aidan O’Brien-trained filly Was won the Investec Oaks on the first day of Investec Derby Festival at Epsom by a neck.

A daughter of Galileo who cost her owners Coolmore 1.2million guineas as a yearling, Was started the race as one of the less-fancied of O’Brien’s five runners.

But once leader Nayarra dropped away, Was swept to the front under Seamus Heffernan and stayed the mile and a half well to see off second-placed Shirocco Star, who ran a terrific race for Darryl Holland and Hughie Morrison, despite getting very worked up in the preliminaries.

The Fugue, the John Gosden-trained 11-4 favourite, was lucky to survive an early bump and did well to finish third ahead of Vow.

O’Brien has now trained the winners of all three British Classics run so far this year, and his 2000 Guineas hero Camelot is red-hot favourite to take the Derby tomorrow.

“Seamus gave her a lovely ride. She’s a very good-looking filly with a great pedigree,” said O’Brien, whose son Joseph will ride Camelot in the Derby. “Seamus knows all the horse inside out [he is the Ballydoyle stable jockey] – no one deserves this more.”