Foaled on February 15, 1974, Seattle Slew was, at the time of his death on May 7, 2002, the only horse to win the American Triple Crown while undefeated. Since then, the only other horse to do so was Justify, in 2018, who is descended from Seattle Slew through perhaps the best known of his offspring, 1992 Horse of the Year A.P. Indy.
Originally trained by William ‘Billy’ Turner Jr. and ridden by French-American jockey Jean Cruguet, Seattle Slew raced just three times as a juvenile. He did, however, win all three starts, including the Grade 1 Champagne Stakes at Belmont Park – at the time, the most important race of its kind in the United States – which was sufficient to be named Champion Two-Year-Old in 1976.
After three preparatory races, in which he was sent off at long odds-on, Seattle Slew duly became the tenth winner of the American Triple Crown, clinching the championship with a comfortable, 4-length victory over Run Dusty Run in the Belmont Stakes, with Cruguet celeberating prematurely, some way from the finish line. Controversy followed, with Seattle Slew managing only a distant fourth, beaten 16 lengths, in the Swap Stakes at Hollywood Park on his next start, a defeat that ultimately led to Turner being fired and replaced by Douglas Peterson. Seattle Slew was beaten twice more as a four-year-old, by a neck and by a nose, but still finished his career with 14 wins from 17 starts and just over $1.2 million in prize money.
Following his retirement from racing, Seattle Slew stood at stud at Spendthrift Farm in Lexington and Three Chimneys Farm in Midway. He eventually died in his sleep at Hill ‘n’ Dale Farm in Paris, Kentucky on May 7, 2002 – 25 years to the day after winning the Kentucky Derby – at the age of 28. Co-owner Mickey Taylor said of him, “He was the most complete Thoroughbred the industy has ever seen. He just kept raising the bar with every record he broke.”