Shamreen will not run again, said her trainer Dermot Weld.
Time has been called on the four-year-old filly's career after she finished last when well fancied for the Prix de l'Opera at Chantilly at the start of the month.
Before that, the Aga Khan-owned daughter of Dubawi had looked on the march after having claimed consecutive victories in big races at the Curragh.
Weld told the Irish Times: "She did us proud winning back-to-back renewals of the Blandford Stakes and landing the Royal Whip as well."
The Rosewell House handler plans to run fellow Aga Khan filly Eziyra on Champions Day at Ascot on Saturday week.
Weld's progressive three-year-old has won her last two races, including the Enterprise Stakes at Leopardstown, and is now poised to contest the Qipco British Champions Fillies & Mares Stakes.
Her trainer said: "Hopefully Eziyra goes to Ascot.
"It's the last big day of the European season and it's been profitable for Pat (Smullen) and myself in the past."
Plans remain fluid for stablemate Zhukova after she finished last in the Grade One Flower Bowl at Belmont on Sunday.
Weld said of the Grade One-winning mare: "They only had a sprinkle of rain in New York. It was firm ground and a mile and a quarter is not ideal for her.
"She's come out of it well and looks magnificent but no decision has been taken on what she does next."