Mahler is a racehorse sired by Galileo

Galileo (horse)

Galileo is a retired Irish Thoroughbred racehorse and active sire. He is best known for winning the Epsom Derby, Irish Derby Stakes, and King George VI and Queen Elizabeth Stakes in 2001 and for his rivalry with the Godolphin champion Fantastic Light...

 out of Rainbow Goddess. During his racing career, he was trained in Ireland

Republic of Ireland

Ireland , described as the Republic of Ireland , is a sovereign state in Europe occupying approximately five-sixths of the island of the same name. Its capital is Dublin. Ireland, which had a population of 4.58 million in 2011, is a constitutional republic governed as a parliamentary democracy,...

 by Aidan O'Brien

Aidan O'Brien

Aidan Patrick O'Brien is an Irish horse racing trainer. Since 1996, he has been the private trainer at Ballydoyle Stables near Cashel in County Tipperary for John Magnier and his Coolmore Stud associates....

, and he is owned by Sue Magnier

John Magnier

John Magnier is Ireland's leading thoroughbred stud owner and has extensive business interests outside of the horse breeding industry....

, Michael Tabor

Michael Tabor

Michael B. Tabor is a businessman and owner of Thoroughbred racehorses.-Thoroughbred racing career:...

 and Derrick Smith.

His most notable victory to date was in the Group 3 Queen's Vase

Queen's Vase

The Queen's Vase is a Group 3 flat horse race in Great Britain open to three-year-old thoroughbreds. It is run at Ascot over a distance of 2 miles , and it is scheduled to take place each year in June.-History:...

 at Ascot Racecourse

Ascot Racecourse

Ascot Racecourse is a famous English racecourse, located in the small town of Ascot, Berkshire, used for thoroughbred horse racing. It is one of the leading racecourses in the United Kingdom, hosting 9 of the UK's 32 annual Group 1 races...

 in Great Britain

Great Britain

Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...

, although a more lucrative performance was to follow in the 2007 Melbourne Cup

2007 Melbourne Cup

The 2007 Melbourne Cup, the 147th running of Australia's most prestigious thoroughbred horse race, was run on Tuesday, November 6, 2007, going at 3:00 pm local time . The race was sponsored by Emirates Airline...

 in Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

, where he finished third when ridden by Stephen Baster.

He now stands as a stallion at Coolmore's

Coolmore Stud

Coolmore Stud, in Fethard, South Tipperary in Ireland, is the world's largest breeding operation of thoroughbred racehorses. It was established in 1975....

 National Hunt

National Hunt racing

National Hunt racing is the official name given to the sport of horse racing in the United Kingdom, France and Ireland in which the horses are required to jump over obstacles called hurdles or fences...

breeding operation in Ireland.