Blood-Horse magazine List of the Top 100 U.S. Racehorses of the 20th Century

In 1999, The Blood-Horse magazine assembled a seven-person panel of distinguished horse racing people: Keeneland racing secretary Howard Battle, Maryland Jockey Club vice president Lenny Hale, Daily Racing Form columnist Jay Hovdey, Sports Illustrated senior writer William Nack, California senior steward Pete Pedersen, Louisville Courier-Journal racing writer Jennie Rees and Gulfstream Park steward Tommy Trotter. Each of the experts compiled a list of what they considered to be the top 100 Thoroughbred racehorses of the 20th century, which was then combined into a master list. The list was expanded into a book with complete biographies.

All the horses on the list raced in the United States, though several such as Phar Lap, Northern Dancer, Dahlia and Miesque began their careers in another country. Ruffian was the top ranked filly.

The small body of voters meant that any individual ballot had the potential to disproportionately influence the final tally, which ended up coming to pass. At the time of the list's unveiling, Blood-Horse managing editor Evan Hammonds spoke to the Associated Press. Hammonds revealed that Secretariat and Man o' War had both received three of the seven first-place votes. (Citation received the other first-place vote.) Man o' War was listed in first, second or third place on all seven ballots; six of the voters gave the same placement to Secretariat. However, Hammonds noted, a single voter left Secretariat out of that person's top 10 "because he got beat a few times". The result was that Secretariat became second, rather than first, in the aggregated final list.

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