Horse of the Week

Diamond Necklace

Thoroughbred racing — Thoroughbred — 3 years old

Diamond Necklace extended her unbeaten record to six with a dominant victory in the Group One Qatar Nassau Stakes.

Photograph of Diamond Necklace

More Photographs

Diamond Necklace — photo 2
Diamond Necklace — photo 3
Diamond Necklace — photo 4
Diamond Necklace — photo 5
Diamond Necklace — photo 6
Diamond Necklace — photo 7
Diamond Necklace — photo 8

The Ledger

Total Wins
6
2026 Wins
3 (Prix Marcel Boussac, French 1000 Guineas, French Oaks)
Race won this week
Qatar Nassau Stakes (Group 1)
Jockey
Ryan Moore
Trainer
Aidan O'Brien
Winning margin
2.75 lengths
Distance of race
1 mile 2 furlongs
Pre-race odds
4/6 favourite
Sire
St Mark's Basilica
Dam's sire line (O'Brien)
Galileo mare

Why This Horse?

  1. Diamond Necklace maintained her perfect unbeaten record, securing her sixth consecutive victory.
  2. She won a prestigious Group 1 race, the Qatar Nassau Stakes, against older fillies for the first time.
  3. Jockey Ryan Moore described her performance as 'very easy really' and noted she's 'improving with her racing.'
  4. She has demonstrated exceptional form this year, including Classic wins in the French 1000 Guineas and French Oaks.
  5. Her victory contributed to Aidan O'Brien's impressive 14th Group 1 win of the season.

Saloon Trivia

  • She is described as a "proper racing machine" and gives a "classy feel" to her jockey.
  • Her father, St Mark's Basilica, was known for his very good turn of foot, a trait evident in Diamond Necklace.
  • She can perform well on both soft and fast ground.
  • Trainer Aidan O'Brien considered her weight before the race but her work rider was confident it was strength, not heaviness.
  • Future options for her include races at York, an Arc trial, or the Prix Rothschild in France, and she could potentially be considered for the Qatar Prix de l'Arc de Triomphe.

Wired in from

Week 2026-W31

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