A useful but not outstanding racehorse, Unbreakable's sole distinction is his place as the sire of 1947 American champion sprinter Polynesian, who in turn sired the great Native Dancer.
14 starts, 5 wins, 3 seconds, 2 thirds, £7,092
- Won Exeter Stakes (ENG, Newmarket)
- Won Richmond Stakes (ENG, 6FT, Goodwood)
- Won Soltykoff Stakes (ENG, Newmarket)
- 3rd Middle Park Stakes (ENG, 6FT, Newmarket)
- 3rd Windsor Castle Stakes (ENG, 5FT, Ascot)
- Won Waterford Stakes (ENG, 8FT, Ascot)
- 2nd Knowsley Dinner Stakes (ENG, 10FT, Liverpool)
- 3rd Sussex Stakes (ENG, 8FT, Goodwood)
- Won Victoria Cup (ENG, 7FT, Hurst)
Ranked sixth among English-raced juvenile males of 1937, 5 pounds below the top.
Earned a Free Handicap rating of 117 pounds at 3, 16 pounds below champion Bois Roussel.
As an individual
A black horse with a commanding presence, Unbreakable had a long neck and good shoulders but was marred by sickle hocks. He did not stay more than 7 furlongs against good company, scoring only against very moderate company at a mile.
As a stallion
According to The Jockey Club, Unbreakable sired 140 winners (64.8%) and 13 stakes winners (6.0%) from 216 named foals.
Unbreakable was bred and owned by Joseph E. Widener. He was trained by Captain Cecil Boyd-Rochfort.
Unbreakable is inbred 5x4x4x5 to nine-time leading English sire St. Simon and 4x4 to 1890 Derby Stakes winner Sainfoin. He is a half brother to 1933 Belmont Stakes winner Hurryoff (by Haste) and multiple stakes winners Blind Play (by Fair Play) and Broadside (by Man o' War). He is also a half brother to Crystal Maze (by Chance Shot), dam of multiple stakes winner Impromptu (by Pavot) and second dam of stakes winners First Blue, I Deceive and Ida, and to Triplex (by Fair Play), second dam of 1947 Chesapeake Stakes winner Bullet Proof, multiple Canadian stakes winner Mr. Infinity and juvenile stakes winner I'm Marie.
Blue Glass, the dam of Unbreakable, is a half sister to 1917 Belmont Stakes winner Hourless, who shared that year's championship honors in the American 3-year-old male division with Kentucky Derby winner Omar Khayyam. A daughter of the Rock Sand mare Hour Glass II, Blue Glass is also a half sister to Hour Hand (by Ethelbert), dam of 1923 Coaching Club American Oaks winner How Fair (by Fair Play) and multiple Canadian stakes winner Horologie (by St. Amant).
Books and media
Unbreakable is profiled along with his sire Sickle in Chapter 26 of Abram S. Hewitt's Sire Lines (1977, The Thoroughbred Owners and Breeders Association; updated and re-released by Eclipse Press in 2006).