Events in Sport
- 1919-08-13 American thoroughbred racehorse Man o' War's only defeat in 21 start career; Upset wins Sanford Memorial Stakes at Saratoga Race Course
45th Preakness
1920-05-18 45th Preakness: Clarence Kummer aboard Man o' War (regarded as greatest racehorse of all time) defeats Upset by 1+1⁄2 lengths in 1:51.6
- 1945-02-05 Big Racket becomes fastest race horse at 69t.6 kph (440 yd/20.8 s)
- 1981-10-02 17-year-old gelding Behavin Jerry, the oldest winning racehorse in modern times, sets record for most career starts by a thoroughbred, 307
Birthdays in Sport
- 1874-03-17 Kincsem, Hungarian horse that never lost a race, born in Kisbér, Hungary (d. 1877)
- 1880-11-30 Herbert Jones, British thoroughbred jockey (British Triple Crown [Diamond Jubilee] 1900; 8 x British Classic Race wins), born in Epsom, England (d. 1951)
- 1917-03-29 Man o' War, American thoroughbred racehorse (Preakness Stakes, Belmont Stakes 1920), foaled at Nursery Stud, Kentucky (d. 1947)
- 1934-10-25 Joe Mercer, English thoroughbred race horse jockey (British flat racing Champion Jockey 1979), born in Bradford, England (d. 2021)
- 1938-04-02 Whirlaway, American thoroughbred racehorse (Triple Crown 1941), born in Lexington, Kentucky (d. 1953)
- 1957-04-04 Kelso, American racehorse, born in Claiborne Farm near Paris, Kentucky (d. 1983)
- 1970-01-28 Mr. Prospector, American thoroughbred racehorse and breeding stallion (most influential sire of his generation), born in Spendthrift Farm, Kentucky (d. 1999)
Secretariat (1970-1989)
1970-03-30 American thoroughbred race horse (Triple Crown, 1973), born in Caroline County, Virginia
Seattle Slew (1974-2002)
1974-02-15 American racehorse (American Triple Crown 1977), born in White Horse Acres Farm, Texas
- 1975-03-23 Alydar, American racehorse (d. 1990)
- 1979-12-14 Michael Owen, English footballer, 1996-2013 (Liverpool; New Castle United; and 3 other teams), sports commentator, and racehorse breeder, born in Chester, England
- 1998-04-02 Pleasantly Perfect, American thoroughbred racehorse (Breeders' Cup Classic 2003; Dubai World Cup 2004), born in Clovelly Farms, Louisiana (d. 2020)
- 2003-04-29 Barbaro, American thoroughbred racehorse (d. 2007)
- 2013-04-11 Arrogate, American thoroughbred racehorse (Breeders' Cup Classic, World's Best Racehorse 2016; Pegasus World Cup, Dubai World Cup 2017), born in Clearsky Farms, Kentucky (d. 2020)
Deaths in Sport
- 1947-11-01 Man o' War, American thoroughbred racehorse (Preakness Stakes, Belmont Stakes 1920), dies from a heart attack at 30
- 1951-07-18 Herbert Jones, British thoroughbred jockey (British Triple Crown [Diamond Jubilee] 1900; 8 x British Classic Race wins), dies by suicide at 70
- 1953-04-06 Whirlaway, American thoroughbred racehorse (Triple Crown 1941), dies at 15
- 1975-07-06 Ruffian, American racehorse (b. 1972)
- 1975-07-07 Ruffian, American thoroughbred racehorse (b. 1972)
- 1983-10-16 Kelso, American racehorse (b. 1957)
Secretariat (1970-1989)
1989-10-04 American thoroughbred race horse (Triple Crown, 1973), euthanized while suffering from laminitis at 19
- 1990-11-15 Alydar, American racehorse (b. 1975)
- 1998-09-27 Narita Brian, Japanese racehorse, world's top earner until 2000 (b. 1991)
- 1999-06-01 Mr. Prospector, American thoroughbred racehorse and breeding stallion (most influential sire of his generation), dies of complications from colic at 29
- 2001-01-12 Affirmed, American racehorse (b. 1975)
Seattle Slew (1974-2002)
2002-05-07 American racehorse (American Triple Crown 1977), dies at 28
- 2007-01-29 Barbaro, American thoroughbred racehorse (b. 2003)
- 2020-06-02 Arrogate, American thoroughbred racehorse (Breeders' Cup Classic, World's Best Racehorse 2016; Pegasus World Cup, Dubai World Cup 2017), dies at 7
- 2020-06-03 Pleasantly Perfect, American thoroughbred racehorse (Breeders' Cup Classic 2003; Dubai World Cup 2004), dies at 22
- 2021-05-17 Joe Mercer, English thoroughbred race horse jockey (British flat racing Champion Jockey 1979), dies at 86