Tommy Stack's Wannabe Better sprouted wings in the closing stages to land the feature race at Leopardstown, the Group Three Ballycorus Stakes.
Held up in midfield by Wayne Lordan as favourite Brendan Brackan set the pace, the 10-1 chance looked to have an enormous amount of ground to make up in the final furlong.
Eastern Rules had hit the front at that point, but he had no answer to Wannabe Better's late charge, and the filly flew home to record a half-length verdict.
Battle Of Marathon showed a smart turn of foot to land the Irish Stallion Farms EBF Maiden under Colm O'Donoghue.
Aidan O'Brien's charge drifted out to 7-1 before the race, but picked up nicely to overtake stablemate Rule The Waves and open up a gap a furlong out.
Favourite I Will Excel ran on to chase home the winner in the closing stages, but was still two and three-quarter lengths adrift at the line.
Royal Memory came from well off the pace to land the Irish Stallion Farms EBF Fillies Maiden for John Oxx and Declan McDonogh.
Odds-on favourite Comtesse, who had beaten Oxx's filly when they met previously, hit the front a furlong out but was soon swamped by 16-1 chance Royal Memory.
Fire Stone came from off the pace to pose the final challenge, but she was half a length down at the finish.
Pit Stop got up in the final strides to land the Leopardstown Summer Music And Racing Festival Handicap.
Michael Halford's 11-8 favourite looked set to sweep clear approaching the furlong pole, but Beyond Brilliance dug deep to fend him off until the final few yards, when Shane Foley got the winner in front.
Naoise (4-1) ran on well to land the 'Heathers' Handicap for Jim Bolger and Kevin Manning.