Aidan O'Brien's Rumplestiltskin landed the Group One Moyglare Stud Stakes at the Curragh under Kieren Fallon.
The Danehill filly was a warm order for the seven-furlong race following her effortless success in the Debutante Stakes at the County Kildare track four weeks ago.
Sent off the 2-7 favourite to enhance her 1000 Guineas credentials, Rumplestiltskin hit the front inside the final furlong but had to battle hard to see off Ugo Fire (25-1) by a neck.
Ardbrae Lady, a 100-1 outsider, finished third.
Fallon settled Rumplestiltskin towards the back of the field and had to drop her right out and pull wide in order to get a run.
She then took a long time to find top gear and after joining Ugo Fire at the head of affairs, looked around and was really pushed to secure first place.
But she started to gain the upper hand in the closing strides and was in command on the line. Chelsea Rose continued her resurgence with a smooth success in the Listed Dance Design Stakes.
Con Collins' three-year-old had bounced back to form at Leopardstown last month when seeing off Irish Field St Leger hopefuls Shalapour and Vinnie Roe in the Ballyroan Stakes.
Sent off the 2-1 favourite on the back of that effort, last year's Group One Moyglare Stud Stakes winner swept into the lead at the furlong pole to beat Pictavia by two lengths.
James Given's Summitville led for most of the way under Jamie Spencer but weakened close home and finished fourth.