Duntle could attempt to settle an old score back in Group One company following her plucky success in the Duke of Cambridge Stakes.
The victory made it two wins out of two for the Irish on day two, taking the overall tally to six with the record standing at eight.
It was to be the last Irish win of the day, though.
David Wachman's vastly progressive filly was demoted into second place on her sole try at the top level, when she was first past the post in the Matron Stakes at Leopardstown last September.
The four-year-old (100-30) has since boosted her profile with a Group Three victory on her return to the fray in May and is to set sail for even greater riches.
Newmarket's Falmouth Stakes and the Prix Jaques le Marois at Deauville in France could now be on the horizon for a horse who was visiting the Royal winner's enclosure for a second successive year yesterday.
Wachman had stressed that the daughter of Danehill Dancer is a reluctant leader but jockey Wayne Lordan had no choice other than to put her to the front a furlong and a half out such was the fluency with which she was travelling.
Most expected early pacemaker Ladys First to give up the ghost once Duntle bustled clear, but Richard Fahey's filly showed plenty of heart to get to within half a length of the winner and book a possible trip to America for the Beverly D Stakes.
Wachman said: "She doesn't win by far, but she does enough.
"The Matron Stakes is in the past, it's history, now we'll try to win another Group One.
"The Falmouth is maybe where we are heading now, there's a race in France and that is also on the agenda."
Compatriot Aidan O'Brien was on the scoresheet for the third time in two days when Gale Force Ten won the opening Jersey Stakes.
The Oasis Dream colt was unsurprisingly a warm order for this Group Three over seven furlongs following his second placed finish in the Irish 2,000 Guineas last month.
However it fleetingly looked like the 9-2 favourite was in a spot of bother once Montiridge nosed ahead inside the final 100 yards.
But Joseph O'Brien's partner, who had been in the lead two and a half furlongs from home, rallied gamely once overtaken to score by a head.
O'Brien snr, who won the Jersey Stakes last year with Ishvana, commented: "Joseph said in an ideal world he would not want to be in front as long as that.
"He could step up to a mile or go back to six furlongs, which is unusual. Over six he would not want to be in front as long as that," he added.
The second afternoon concluded with a first Royal winner for trainer Johnny Portman as the Richard Kingscote-ridden Annecdote prevailed in the Sandringham Handicap.
Uleavemebreathless, trained in Caledon, Co Tyrone by Andy Oliver and ridden by Chris Hayes, was 10th of the 26 runners.
Oliver will now turn his attention to the two-day Ulster Derby meeting at Down Royal which starts tomorrow.