Diamond Necklace secured victory in the Group 1 Prix de Diane over 2,100 meters at Chantilly on June 14, 2026, maintaining her unbeaten record with five wins from five starts [1, 2, 3]. The race featured 11 runners and carried a prize of €1 million (S$1.48 million) [1, 2, 3].
Ridden by jockey Ryan Moore, Diamond Necklace faced a fast pace set by stablemate Moments Of Joy and competitor Esna. Moore positioned her wide in the straight to mount a strong finish [1, 2, 3]. The filly narrowly held off 20-1 outsider Inis Mor and 50-1 Pink Panthera, who briefly led before being overtaken near the line [1, 2, 3].
Trainer Aidan O’Brien marked his second Prix de Diane triumph with Diamond Necklace, following Joan Of Arc’s 2021 win. This marked O’Brien’s seventh spring Classic victory from 10 attempts across France, England, and Ireland in 2026 [1, 2, 3]. His other major wins this season include Precise in the Irish 1,000 Guineas, Gstaad in the Irish 2,000 Guineas, True Love in the English 1,000 Guineas, Christmas Day in the Epsom Derby, and Constitution River in the Prix du Jockey Club [1, 2, 3].
Diamond Necklace had previously won the Poule d’Essai des Pouliches (French 1,000 Guineas) earlier this year [1, 2, 3]. O’Brien said, "We have always believed she possessed tremendous class. She was unbeaten last year. Ryan gave her a wonderful ride in the Guineas this season, just as he did today" [2].