Ruperto Donoso was a jockey

Jockey

A jockey is an athlete who rides horses in horse racing or steeplechase racing, primarily as a profession. The word also applies to camel riders in camel racing.-Etymology:...

 in the sport of Thoroughbred

Thoroughbred

The Thoroughbred is a horse breed best known for its use in horse racing. Although the word thoroughbred is sometimes used to refer to any breed of purebred horse, it technically refers only to the Thoroughbred breed...

 horse racing

Horse racing

Horse racing is an equestrian sport that has a long history. Archaeological records indicate that horse racing occurred in ancient Babylon, Syria, and Egypt. Both chariot and mounted horse racing were events in the ancient Greek Olympics by 648 BC...

 best known for riding Phalanx

Phalanx (horse)

Phalanx was an American Champion Thoroughbred racehorse. He was sired by Pilate, a son of the 1916 Belmont Stakes winner, Friar Rock. His dam was the outstanding runner, Jacola, the American Champion Two-Year-Old Filly of 1937 who beat the great Seabiscuit by two lengths in the 1938 Laurel Stakes....

 to victory in the 1947 Belmont Stakes

Belmont Stakes

The Belmont Stakes is an American Grade I stakes Thoroughbred horse race held every June at Belmont Park in Elmont, New York. It is a 1.5-mile horse race, open to three year old Thoroughbreds. Colts and geldings carry a weight of 126 pounds ; fillies carry 121 pounds...

. He also rode Gilded Knight to a second place finish in the 1939 Preakness Stakes

Preakness Stakes

The Preakness Stakes is an American flat Thoroughbred horse race for three-year-olds held on the third Saturday in May each year at Pimlico Race Course in Baltimore, Maryland. It is a Grade I race run over a distance of 9.5 furlongs on dirt. Colts and geldings carry 126 pounds ; fillies 121 lb...

.

A native of Santiago, Chile

Santiago, Chile

Santiago , also known as Santiago de Chile, is the capital and largest city of Chile, and the center of its largest conurbation . It is located in the country's central valley, at an elevation of above mean sea level...

, before going to the United States, Donoso rode in Santiago and at the Hipódromo de Monterrico

Hipódromo de Monterrico

The Hipódromo de Monterrico is a Thoroughbred horse racing facility opened in 1960 in Lima, Peru. Operated by the Jockey Club del Peru, it has a one and one-eight mile dirt racetrack with a one mile inside track for turf racing....

 in Lima

Lima

Lima is the capital and the largest city of Peru. It is located in the valleys of the Chillón, Rímac and Lurín rivers, in the central part of the country, on a desert coast overlooking the Pacific Ocean. Together with the seaport of Callao, it forms a contiguous urban area known as the Lima...

, Peru

Peru

Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....

. http://www.lanacion.cl/prontus_triunfo/site/artic/20090324/pags/20090324185644.html

Ruperto Donoso was required to do mandatory service with the Chilean Army

Chilean Army

The Chilean Army is the land arm of the Military of Chile. This 45,000-person army is organized into seven divisions, a special operations brigade and an air brigade....

 and as such did not race in 1942 and 1943, returning on July 24, 1944 to compete at New Yorks Belmont Park

Belmont Park

Belmont Park is a major thoroughbred horse-racing facility located in Elmont in the Town of Hempstead in Nassau County, New York, on Long Island adjoining New York City. It first opened on May 4, 1905...

. In the 1947 U.S. Triple Crown

United States Triple Crown of Thoroughbred Racing

In the United States, the "Triple Crown" is usually the Triple Crown of Thoroughbred Racing, a series of three Thoroughbred horse races for three-year-old horses run in May and early June of each year consisting of the Kentucky Derby, Preakness Stakes, and Belmont Stakes.While Daily Racing Form...

 series, superstar jockey Eddie Arcaro

Eddie Arcaro

George Edward Arcaro , known professionally as Eddie Arcaro, was an American Thoroughbred horse racing Hall of Fame jockey who won more American classic races than any other jockey in history and is the only rider to have won the U.S. Triple Crown twice...

 rode Phalanx to a second-place finish in the Kentucky Derby

Kentucky Derby

The Kentucky Derby is a Grade I stakes race for three-year-old Thoroughbred horses, held annually in Louisville, Kentucky, United States on the first Saturday in May, capping the two-week-long Kentucky Derby Festival. The race is one and a quarter mile at Churchill Downs. Colts and geldings carry...

 and to a third in the Preakness Stakes

Preakness Stakes

The Preakness Stakes is an American flat Thoroughbred horse race for three-year-olds held on the third Saturday in May each year at Pimlico Race Course in Baltimore, Maryland. It is a Grade I race run over a distance of 9.5 furlongs on dirt. Colts and geldings carry 126 pounds ; fillies 121 lb...

. It was then that trainer Syl Veitch

Sylvester Veitch

Sylvester E. Veitch was a Hall of Fame thoroughbred horse trainer.Veitch began his career in racing as a jockey and trainer in Steeplechase racing. In 1939 he moved to flat racing when he began employment as a trainer with Cornelius Vanderbilt Whitney in Kentucky...

 decided to replace Arcaro with the C. V. Whitney

Cornelius Vanderbilt Whitney

Cornelius Vanderbilt Whitney was an American businessman, film producer, writer, and government official, as well as the owner of a leading stable of thoroughbred racehorses....

stable's secondary jockey in the Belmont Stakes. Donoso had ridden Phalanx to two wins in 1946 but as the stable's first string jockey, Arcaro had had first choice on all mounts. http://news.google.com/newspapers?id=3MMKAAAAIBAJ&sjid=5U4DAAAAIBAJ&pg=3671,1994506&dq=donoso+belmont+stakes