Innisfree continued Aidan O'Brien's total domination of the Group 2 Beresford Stakes when denying Shekhem by a neck in a rousing finish at the Curragh.
Winner of a Galway maiden in July by the same margin from the same rival, the son of Galileo was making it nine straight wins in the race and 19 in total for O'Brien, following the likes of Japan, Saxon Warrior and St Nicholas Abbey.
Winning rider Donnacha O'Brien said: "It went smoothly. Chris [Hayes on Shekhem] went a nice, even gallop. My lad travelled well and brought me into the race really nicely and toughed it out in the final furlong."
O'Brien is yet to have a Beresford winner go on to score in the Derby and Innisfree was quoted at 33-1 by Paddy Power for Epsom with the market dominated by this year's standout juvenile Pinatubo at 8-1.
The victory of Innisfree in the Group 2 Beresford Stakes at the Curragh on Sunday provided an all-round success for the first family of Irish racing.
The son of Galileo was bred by Aidan and Annemarie O'Brien's Whisperview Trading and is trained by Aidan at Ballydoyle, with Annemarie registered as joint-owner with Derrick Smith, Susan Magnier and Michael Tabor.
To put the icing on the cake, Innisfree was partnered to his neck success from the Aga Khan's Zoffany colt Shekhem by Aidan and Annemarie's son Donnacha.
So multi-skilled and mighty are the O'Briens that Innisfree is not the first Group winner where the family have made up many of the connections.
Mohawk, winner of the Royal Lodge Stakes last year and Meld Stakes in July, was ridden by Donnacha, trained by Aidan and bred by Whisperview, while 2016 Moyglare Stud Stakes heroine Intricately was also Whisperview-bred and ridden by Donnacha but trained by his brother Joseph.
In his riding career Joseph was aboard several Group winners bred and trained by his parents, including Cougar Mountain, Empowering, Furner's Green and Kingsbarns.
Innisfree is the second foal out of Palace, a Listed-winning daughter of Fastnet Rock who has also produced Royal Aide, another son of Galileo who has won competitive handicaps at Killarney and Bellewstown for Joseph O'Brien this summer.
Palace is a half-sister to Furner's Green, a Group 3 winner who died after his fast-finishing close third in the Poule d'Essai des Poulains, as well as Irish Oaks third Lady Lupus and Listed scorer Mystical Lady, who produced Gold Cup and Irish Derby second Kingfisher at paddocks.
Palace, Furner's Green and co are out of Lady Icarus, an unraced daughter of Rainbow Quest and champion Sonic Lady, whose victories included the Irish 1,000 Guineas, Sussex Stakes, Prix du Moulin, Coronation Stakes and the Falmouth Stakes (then Child Stakes) twice.
Despite having that wonderful pedigree, Lady Icarus was bought as a nine-year-old by Annemarie O'Brien for just €25,000 from the Darley draft at the Goffs November Breeding-Stock Sale in 2004, when she was carrying a Halling foal who would turn out to be Mystical Lady.
Innisfree becomes stakes winner number 307 for Coolmore's perennial champion sire Galileo and the first of those to be out of a daughter of Fastnet Rock.
The reverse cross, Fastnet Rock over Galileo mares, has been heavily mined and come up trumps with Group 1 winners Age Of Fire, Intricately, Magicool, Qualify, Rivet, Unforgotten and Zhukova.