Octagonal, Australia's Horse of the Year in 1996, was euthanized at Godolphin Woodlands Oct. 15, according to Darley.
"The Big O" as he was affectionately known, was 24 and still alert mentally but was struggling physically.
Octagonal was bred at Cambridge Stud in New Zealand and was from the first crop of champion sire Zabeel. Purchased by Jack and Bob Ingham, he was trained by John Hawkes at their headquarters Crown Lodge.
Oct. 22 marks the 21st anniversary of Octagonal's victory as a 3-year-old in the BMW Cox Plate (Aus-I). The following fall he won the 3-year-old Triple Crown of the Canterbury Guineas (Aus-I), Rosehill Guineas (Aus- I), and Australian Derby (Aus-I).
As a 5-year-old, he recorded his 10th group I win in the Mercedes Classic, a victory that saw him become the highest-earning horse in Australian racing history at the time.
Retired to stud in 1997 he sired Australian Horse of the Year Lonhro in his first crop. An 11-time group I winner, Lonhro is the only Australian Horse of the Year to go on and become a champion stallion.
"It is a sad day, as Octagonal is an old favorite of everyone and he will be sorely missed," said John Sunderland, general manager at Woodlands. "He was such a lovely horse to deal with and such a big part of Woodlands."
Octagonal will be buried at Woodlands, where he has spent the majority of the past 16 years, alongside his old mate Canny Lad.